Impact of blood pressure control on left atrial diastolic function as determined by 2D speckle tracking echocardiography

doi:10.21203/rs.3.rs-4724233/v1

Aim and Objectives:

The study's objective is to investigate, in recently diagnosed individuals with systemic hypertension, the impact of appropriate blood pressure control on left atrial functions as assessed by 2D speckle echocardiography and electrocardiogram.

Patients and Methods:

Fifty patients with newly diagnosed systemic arterial hypertension who presented to Ain Shams University Hospitals were included in the study. The patients' demographic information, risk factors, general and local examinations, 12-lead ECGs, 2D speckle tracking echocardiograms, and laboratory measurements were evaluated. Following six months of appropriate blood pressure (BP) control in accordance with JNC 10, the patients were followed up.

Results

PALS (peak atrial longitudinal strain) increased in the current study, with a mean change of 35.04 ± 4.33 to 38.92 ± 5.52 and a P-value < 0. 001. The mean of PACS (peak atrial contraction strain) increased from 17.38 ± 4.67 to 20.46 ± 4.39, with a P-value of less than 0.001. The mitral peak early (E) and the septal mitral annular velocities (e`) and their average E/e' showed decrease with change of the mean from 8.8 ± 0.93 to 7.8 ± 1.16, with a P-value of less than 0.001. The mean of the left atrial stiffness index (LASI) decreased from 0.24 ± 0.04 to 0.2 ± 0.03, with a P-value less than 0.001. The ECG follow-up showed no discernible change in the P wave's duration or amplitude with P values of 0.135 and 0.785 respectively.

Conclusion

The results of this study showed that patients with hypertension may benefit from using speckle tracking imaging to identify mild impairment of left atrial (LA) function. PALS, PACS, E/e', and LASI improve in hypertensive patients when blood pressure is well controlled. Further research is warranted to better understand the significance of LA function using speckle tracking echocardiography (STE) in the prediction of atrial fibrillation and the risk of heart failure with preserved ejection fraction. This study highlights how important it is to measure LA function in hypertensive patients.

Health sciences/Diseases/Cardiovascular diseases/Hypertension

Health sciences/Health care/Medical imaging/Ultrasonography/Echocardiography

Hypertension

Left atrium strain

Left atrium stiffness index

Intra-atrial conduction delay

Hypertension can quietly damage the body for years before symptoms develop. Uncontrolled hypertension can lead to disability, a poor quality of life, or even a fatal myocardial infarction or stroke.(1) Transthoracic echocardiography (TTE) is the first imaging modality of choice for the evaluation of LA volume index (LAVI) and function. However, TTE allows new approaches for LA anatomical and functional analysis such as (LASI) calculation based on LA global longitudinal strain (GLS).(2) The left atrium can be regarded as a dynamic continuum of the left ventricle with a principal role of ensuring left ventricular (LV) filling and cardiac performance by its reservoir, conduit, and booster pump function. This 3-phase role depends not only on LV diastolic and systolic function but also on intrinsic LA properties. As such, any alteration in ventricular performance or loading condition may affect the interdependence between the left atrium and the left ventricle.(3) Left atrium enlargement has been proven to be associated with ischemic stroke and cardiovascular disease.(4) Speckle tracking echocardiography (STE) allows direct and angle-independent analysis of myocardial deformation, thus providing sensitive and reproducible indices of myocardial fiber dysfunction that overcome most of the limitations of Doppler-derived strain measures.(5)

Objective:

To study the effect of adequate blood pressure control on left atrial functions measured by 2D echocardiography in newly diagnosed patients with systemic hypertension.

The study was conducted in Ain Shams University hospitals on 50 patients presented with established systemic arterial hypertension. All patients were adequately controlled on medications at follow up. Proper history for demographical data, risk factors, the current treatment, general and local examination with emphasis on blood pressure (BP), heart rate (HR) and heart sounds

Approval was obtained from the ethical committee at Ain shams University before starting the research.

All participants had an informed written consent with consideration of adequate privacy and confidentiality.

The Inclusion criteria were: Both sexes, Age > 18 years old, and recently diagnosed systemic arterial hypertension within 6 to 12 months, on antihypertensive medications uncontrolled according to JNC 8 guidelines.(6) While the exclusion criteria were: Patients < 18 years old, Patients having Acute coronary syndrome (ACS) or Chronic coronary Syndrome (CCS), Patients having valvular affection, Patient having atrial arrhythmias, Patient with (left ventricle ejection fraction [LVEF] < 50 and Patients with comorbidities as thyroid dysfunction.

Type of the Study

Prospective observational cohort study

Methods

Checklist for assessment of all the clinical data relevant to the patients. All these sheets were collected then the data entry was carried out through a computer system to establish a data-based system for all the patients and all the collected data were applied to adequate confidentiality.

All patients after written informed consent were subjected to the following at baseline:

Careful history taking including: Clinical, Demographic data including age and sex, Risk factors, Co-morbidities including smoking, diabetes, obesity, dyslipidemia, and presence of family history.

Duration of the study: Study started from October 2022 to July 2023, Collection of the patients at base line from October 2022 to November 2022, follow up ECG and Echocardiography were done after 6 months from proper control of BP to be below 140 Systolic BP and below 90 Diastolic BP according to JNC 8 guidelines.(6)

Comprehensive Physical examination including Vital signs including Blood pressure, heart rate and Auscultation of the heart and lungs.

Investigations: 12 lead surface ECG: with special emphasis on P wave amplitude and P wave duration, CBC, Creatinine, Sodium and potassium, Trans-thoracic Echocardiography.

Two-dimensional (2D) speckle tracking echocardiography (STE):

Vivid e95 GE Healthcare cardiac ultrasound with a multifrequency transducer (3-8MHz) was used to perform the echocardiography. All patients had standard transthoracic echocardiography (TTE) study in the four windows (Parasternal, Apical, Subcostal, and Suprasternal). All studies were performed by a single cardiologist.

Apical four and two chamber view images of the LA were obtained using conventional 2-dimensional echocardiography, at relatively high frame rates (60– 80 fps). The LA endocardium was traced in both four and two chamber views and the region of interest (ROI) was adjusted to the left atrium. In regions of discontinuities of the LA wall, such as areas corresponding to pulmonary veins and LA appendage, extrapolation of the LA endocardial and epicardial surfaces at the junction of these structures was performed to obtain the ROI.

The ROI was divided into six segments and the totals of 12 segments were analyzed with the software generating the individual segmental longitudinal strain curves together with global strain in each view. Also used to measure (PALS, peak atrial longitudinal strain) or LA systolic strain and (PACS, peak atrial contraction strain) or late diastolic strain.

The mitral peak early (E) and atrial contraction (A) flow velocities, septal mitral annular velocities (e`) used as a measure to determine diastolic function, mitral inflow signals were obtained by pulsed wave Doppler echocardiography. Early diastolic inflow velocity (E), velocity during active atrial contraction (A), and E to A wave (E/A) ratio.

Left atrial volume index (LAVI) was measured: the volume was assessed by the biplane area-length method from apical 4- and 2-chamber views. Measurements were obtained in end systole from the frame preceding mitral valve opening, and the volume was indexed for body surface area.

LV systolic function: Was measured in 2D apical 4-chamber and 2-chamber views using biplane method of discs (modified Simpson’s rule).

LA emptying fraction (LAEF) was calculated using biplane Simpson’s method with the following formula: (LA maximum volume–LA minimum volume)/LA maximum volume × 100.

LA max volume: LA volume at end-systole, immediately before mitral valve opening.

LA minimum volume: LA volume at end-diastole, immediately before mitral valve closure.

Left atrial stiffness index (LASI) calculation based on global longitudinal strain (GLS), LASI was calculated as the ratio of E/e` to LA-GLS.

Follow up data:

All enrolled patients should have their blood pressure properly controlled according to JNC 8 guidelines and followed up BP after one week of increasing medication dose and then monthly at our outpatient clinics.

ECG and Echocardiography assessment were performed for all patients with the above-mentioned baseline parameters reassessed after 6 months of properly controlled blood pressure and then both data were compared for each patient.

Statistical Analysis

Data were collected, revised, coded and entered to the Statistical Package for Social Science (IBM SPSS) version 20. Qualitative data were presented as number and percentages while quantitative data were presented as mean, standard deviations and ranges when parametric and median with interquartile ranges (IQR) when nonparametric.

The comparison between two groups with qualitative data were done by using Chi-square test and/or Fisher exact test was used instead of Chi-square test when the expected count in any cell was found less than 5.

The comparison between two groups regarding quantitative data with parametric distribution was done by using independent t-test while data with non-parametric distribution was done using Mann-Whitney test.

The comparison between more than two groups regarding quantitative data with parametric distribution was done by using One Way ANOVA while data with non-parametric distribution was done using Kruskal Wallis test.

The confidence interval was set to 95% and the margin of error accepted was set to 5%. So, the p-value was considered significant as the following: P > 0.05: Non-significant (NS), P < 0.05: Significant (S), P < 0.01: Highly significant.(HS)

The study was conducted on 50 patients who were newly diagnosed with systemic hypertension, uncontrolled. Presented to outpatient clinic in Ain Shams University hospital to properly control BP according to JNC 8 guidelines, history and examination were done regarding demographic data, co-morbidities.

Description of the baseline BP and follow up BP after 6 months for the patients:

Base line mean systolic BP was 149.5 ± 24.9/ mean diastolic BP mean was 90.1 ± 11.0, at the end of the follow-up the mean systolic blood pressure was 134.4 ± 15.7/ mean diastolic BP was 79 ± 9 mm Hg (p = 0.005 Systolic BP and p = 0.01 Diastolic BP)

Description of the demographic data and risk factors among all studied population:

The mean age of the study group was 51.26 years ± 6.39 ranging from 40 to 62, with 28% males and 72% females. Eleven patients (22%) were smokers.

All the patients included in our study their blood pressure was uncontrolled was above 140/90 mmHg at the time of examination then proper blood pressure control below 140/90 mmHg with life style modification and medications, blood pressure measurements at follow up were done monthly at our outpatient clinic [Table 1].

Table 1

Demographic data and characteristics of the studied patients
		Total No. = 50
Age	Mean ± SD	51.26 ± 6.39
Age	Range	40–62
Sex	Female	36 (72.0%)
Sex	Male	14 (28.0%)
BMI	Mean ± SD	30.74 ± 4.68
BMI	Range	24–41
Duration since diagnosis	6 month	30 (60.0%)
Duration since diagnosis	1 year	20 (40.0%)
Drugs	BB(bisoprolol)	26 (52.0%)
	ACEI and ARBS	18 (36.0%)
	CCB	6 (12.0%)
Smoker	Non smoker	88 (78.0%)
Smoker	smoker	11 (22.0%)

Description of the baseline ECG and Echocardiography parameters for the patients:

Base line ECG parameters included amplitude of the P-wave which ranged from 0.16 mV to 0.21 mV, the mean was 0.19 ± 0.01 ( all with in normal range below 0.25 mV), P wave duration which ranged from 80 ms to 100 ms with a mean 89.22 ± 5.96 ( all with in normal range).

Base line echocardiography parameters included ejection fraction ranged from 55–66% with a mean 60.92 ± 3.47, PALS ( reservoir strain ) ranged from 22 to 43 with a mean 35.04 ± 4.33, PACS (peak atrial contraction strain) ranged from 7 to 25 with a mean 17.38 ± 4.67,E wave ranged from 0.4 m/s to 1.02 m/s with a mean 0.68 ± 0.17, A wave ranged from 0.59 m/s to 1.08 m/s with a mean 0.82 ± 0.12, E/A wave ranged from 0.57 to 1.19 with a mean 0.83 ± 0.16, E/e' ranged from 6.21 to 10 with a mean 8.8 ± 0.93, empty fraction ranged from 53%to 70% with a mean 64.68 ± 5.02, left atrium volume index ranged from 20 ml/m2 to 33 ml/m2 with a mean 27.12 ± 2.97 and left atrium stiffness index ranged from 0.18 to 0.33 with a mean 0.24 ± 0.04.

Table 2

Baseline ECG and ECHO parameters among the studied patients
Baseline		Total No. = 50
ECG
P Wave amplitude (mV)	Mean ± SD	0.19 ± 0.01
P Wave amplitude (mV)	Range	0.16–0.21
P-Wave duration (ms)	Mean ± SD	89.22 ± 5.96
P-Wave duration (ms)	Range	80–100
ECHO
EF %	Mean ± SD	60.92 ± 3.47
EF %	Range	55–66
PALS	Mean ± SD	35.04 ± 4.33
PALS	Range	22–43
PACS	Mean ± SD	17.38 ± 4.67
PACS	Range	7–25
E wave	Mean ± SD	0.68 ± 0.17
E wave	Range	0.4–1.02
A wave	Mean ± SD	0.82 ± 0.12
A wave	Range	0.59–1.08
e'	Mean ± SD	0.08 ± 0.02
e'	Range	0.06–0.11
E/e'	Mean ± SD	8.8 ± 0.93
E/e'	Range	6.21–10
E/A	Mean ± SD	0.83 ± 0.16
E/A	Range	0.57–1.19
Diastolic Dysfunction	No	8 (16.0%)
Diastolic Dysfunction	Yes	42 (84.0%)
LAVI	Mean ± SD	27.12 ± 2.97
LAVI	Range	20–33
Emptying fraction	Mean ± SD	64.68 ± 5.02
Emptying fraction	Range	53–70
Max Vol	Median (IQR)	34(29–44)
Max Vol	Range	14–55
Min Vol	Median (IQR)	12(8–14)
Min Vol	Range	3–23
LASI	Mean ± SD	0.24 ± 0.04
LASI	Range	0.18–0.33

Description of the ECG parameters at base line and after 6 months of properly controlled blood pressure

Table 3

ECG at baseline and follow-up after 6 months among the studied patients
		Baseline	After 6 months	% of change	Test value	P-value	Sig.
				Median (IQR)
P Wave amplitude (mV)	Mean ± SD	0.19 ± 0.01	0.19 ± 0.01	0 (0–0)	-1.520•	0.135	NS
	Range	0.16–0.21	0.16–0.21
P Wave duration (ms)	Mean ± SD	89.22 ± 5.96	89.30 ± 5.89	0 (0–0)	-0.275•	0.785	NS
	Range	80–100	80–100
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant
•: Paired t-test

There was no statistically significant difference between P wave duration and amplitude between baseline and six month follow up after proper control of blood pressure. P wave duration and amplitude were within normal range.

Table 4

ECHO at baseline and follow-up after 6 months of properly controlled blood pressure among the studied patients
		Baseline	After 6 months	% of change	Test value	P-value	Sig.
				Median (IQR)
EF %	Mean ± SD	60.92 ± 3.47	60.92 ± 3.47	–	0.000	1.000	NS
	Range	55–66	55–66
PALS	Mean ± SD	35.04 ± 4.33	38.92 ± 5.52	7.71 (3.33–13.89)	-7.768•	< 0.001	HS
	Range	22–43	27–53
PACS	Mean ± SD	17.38 ± 4.67	20.46 ± 4.39	10 (7.14–26.67)	-9.182•	< 0.001	HS
	Range	7–25	10–32
E wave	Mean ± SD	0.68 ± 0.17	0.69 ± 0.16	2.27(-12.86–15.15)	-0.215•	0.830	NS
	Range	0.4–1.02	0.45–1.07
A wave	Mean ± SD	0.82 ± 0.12	0.84 ± 0.15	0(-9.46–7.41)	-0.931•	0.357	NS
	Range	0.59–1.08	0.6–1.16
e'	Mean ± SD	0.08 ± 0.02	0.08 ± 0.01	0(-10–12.5)	-0.522•	0.604	NS
	Range	0.06–0.11	0.06–0.11
E/e'	Mean ± SD	8.8 ± 0.93	7.8 ± 1.16	-9.01 (-16.38 – -3.09)	6.484•	< 0.001	HS
	Range	6.21–10	5.1–9.8
E/A	Mean ± SD	0.83 ± 0.16	0.83 ± 0.16	-0.59(-11.54–14.93)	0.149•	0.882	NS
	Range	0.57–1.19	0.61–1.4
Diastolic Dysfunction	No	8 (16.0%)	8 (16.0%)	–	0.000*	1.000	NS
	Yes	42 (84.0%)	42 (84.0%)
LAVI	Mean ± SD	27.12 ± 2.97	27.12 ± 2.97	–	0.000	1.000	NS
	Range	20–33	20–33
Emptying fraction	Mean ± SD	64.68 ± 5.02	64.68 ± 5.02	–	0.000	1.000	NS
	Range	53–70	53–70
Max Vol	Median (IQR)	34 (29–44)	34 (23–38)	-5.41 (-17.78–6.67)	-1.733≠	0.083	NS
	Range	14–55	13–54
Min Vol	Median (IQR)	12(8–14)	11(6–13)	0(-26.67–8.33)	-1.345≠	0.179	NS
	Range	3–23	2–23
LASI	Mean ± SD	0.24 ± 0.04	0.2 ± 0.03	-13.64 (-24 – -8)	9.090•	< 0.001	HS
	Range	0.18–0.33	0.16–0.31
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant
*: Chi-square test; •: Paired t-test; ≠: Wilcoxon Signed Ranks test

Description of echocardiography parameters at baseline and after 6 months of properly controlled blood pressure table (4):

There's strong relationship between control of blood pressure and change in PALS, PACS, E/e' and LASI as shown: PALS showed increase with change of the mean from 35.04 ± 4.33 to 38.92 ± 5.52 with P-value below 0.001. PACS showed increase with change of the mean from 17.38 ± 4.67 to 20.46 ± 4.39 with P-value below 0.001. E/e' showed decrease with change of the mean from 8.8 ± 0.93 to 7.8 ± 1.16 with P-value below 0.001. LASI showed decrease with change of the mean from 0.24 ± 0.04 to 0.2 ± 0.03 with P-value below 0.001. There was no statistically significant difference between baseline EF and after 6 months as measured by modified biplane Simpson’s method.

Description of the correlation between age, BMI and Echo parameters:

E and A waves were positive correlated with age correlation coefficient 0.4 with P-value 0.002 for the E wave and 0.001 for the A wave, yet it showed mild change

E wave was higher in patients with BMI 30 and more with P-value 0.034

Table 5

Correlation of changes of ECHO parameters with age and BMI among the studied parameters
% of change	Age		BMI
% of change	r	P-value	r	P-value
P Wave	-0.146	0.313	-0.068	0.639
P-R interval	-0.063	0.664	-0.053	0.716
PALS	-0.277	0.051	-0.107	0.460
PACS	0.011	0.940	0.085	0.558
E wave	0.421**	0.002	0.301*	0.034
A wave	0.450**	0.001	0.127	0.381
e'	0.202	0.160	0.230	0.108
E/e'	0.147	0.307	0.127	0.381
E/A	0.032	0.826	0.010	0.943
Maximum Volume	-0.058	0.689	-0.172	0.233
Minimum Volume	-0.165	0.253	0.136	0.348
LASI	0.193	0.178	-0.042	0.774
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant
Spearman correlation coefficient

Table 6

Relation between gender and changes of ECHO parameters among the studied patients
% of change		Sex		Test value	P-value	Sig.
		Female	Male
		No. = 36	No. = 14
PALS	Median (IQR)	1.28(-2.86–12.13)	3.45(0–13.51)	-0.400≠	0.689	NS
	Range	-23.91–34.29	-18.52–40.54
PACS	Median (IQR)	8.7(-4.55–18.93)	0(0–10)	-0.674≠	0.500	NS
	Range	-33.33–157.14	-37.5–87.5
E wave	Median (IQR)	4.17(-9.93–14.72)	-3.51(-15.71–20.45)	-0.735≠	0.462	NS
	Range	-24.74–30	-36.11–25
A wave	Median (IQR)	0(-10.64–7.41)	1.33(-3.53–7.46)	-0.606≠	0.545	NS
	Range	-98.72–37.29	-11.84–17.86
e'	Median (IQR)	0(0–14.29)	0(-14.29–0)	-1.639≠	0.101	NS
	Range	-45.45–66.67	-27.27–33.33
E/e'	Median (IQR)	-1.46(-15.89–4.67)	-9.49(-26.44–3.06)	-1.383≠	0.167	NS
	Range	-25.29–43.33	-43.33–42.77
E/A	Median (IQR)	-1.38(-11.54–5.75)	5.42(-13.64–17.54)	-0.627≠	0.531	NS
	Range	-27.36–37.25	-35.11–22.58
Maximum Volume	Median (IQR)	-2.27(-17.24–7.75)	-12.39(-20.69 – -2.17)	-1.405≠	0.160	NS
	Range	-32.08–80	-36.36–33.33
Minimum Volume	Median (IQR)	0(-26.43–33.33)	-16.03(-26.67 – -6.25)	-1.432≠	0.152	NS
	Range	-81.82–228.57	-44.44–53.33
LASI	Median (IQR)	-8.55(-16.59–4.88)	-12.5(-30.3–0)	-1.364≠	0.173	NS
	Range	-32.14–35	-37.5–29.41
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant
≠: Mann-Whitney test

Description between different types of drugs in relation to changes in echocardiography parameters:

Different types of drugs showed no statistically significant difference between type of the drug and changes in echocardiography parameters after 6 months of proper blood pressure control.

Table 7

Relation between types of drugs and changes of ECHO parameters among the studied patients
		Drugs			Test value	P-value	Sig.
		BB	ACEI and ARBS	CCB
		No. = 26	No. = 18	No. = 6
PALS	Median (IQR)	5.88 (-2.7–12.9)	0 (-11.11–13.51)	1.72 (-2.5–3.45)	2.126≠	0.345	NS
	Range	-23.91–34.29	-18.52–40.54	-4.88–5
PACS	Median (IQR)	8.89 (0–26.09)	0 (-18.75–10.53)	0 (0–8.33)	1.653≠	0.438	NS
	Range	-33.33–57.14	-37.5–157.14	0–8.33
E wave	Median (IQR)	6.54 (-7–21.28)	-3.51 (-15.71–14.29)	5.45 (-4.26–13.33)	2.023≠	0.364	NS
	Range	-24.74–30	-36.11–25	-4.26–13.33
A wave	Median (IQR)	0 (-9.46–15.58)	1.52 (-1.27–7.46)	-11.84 (-98.72–1.33)	4.888≠	0.087	NS
	Range	-27.71–37.29	-15.24–17.86	-98.72–1.33
e'	Median (IQR)	0 (0–14.29)	0 (-11.11–12.5)	0 (-27.27–22.22)	0.531≠	0.767	NS
	Range	-45.45–33.33	-14.29–66.67	-27.27–22.22
E/e'	Median (IQR)	1.05 (-16.38–11.95)	-14.18 (-15.89–0)	-7.3 (-9.49–3.06)	2.395≠	0.302	NS
	Range	-25.29–43.33	-43.33–42.77	-9.49–3.06
E/A	Median (IQR)	-1.38 (-10.47–16.46)	0.41 (-13.64–4.29)	17.54 (-11.54–22.58)	2.401≠	0.301	NS
	Range	-27.36–37.25	-35.11–14.93	-11.54–22.58
Maximum Volume	Median (IQR)	0 (-17.78–20.69)	-3.36 (-13.16–3.33)	-17.24 (-17.78 – -11.63)	5.150≠	0.076	NS
	Range	-32.08–80	-36.36–33.33	-32.08 – -11.63
Minimum Volume	Median (IQR)	0 (-7.69–33.33)	-6.25 (-26.67–8.33)	-33.09 (-53.85 – -21.74)	4.157≠	0.125	NS
	Range	-81.82–228.57	-50–155.56	-53.85–53.33
LASI	Median (IQR)	-10.1 (-17.39–5.26)	-9.2 (-29.63–0)	-6.08 (-10–0)	1.017≠	0.601	NS
	Range	-32.14–35	-37.5–29.41	-15–0
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant ≠: Kruskal-Wallis test

Table 8

Relation between smoking and changes of ECHO parameters among the studied patients
% of change		Smoker		Test value	P-value	Sig.
		No	Yes
		No. = 39	No. = 11
PALS	Median (IQR)	5 (-2.86–12.9)	3.23 (-11.11–5)	-0.645≠	0.519	NS
	Range	-23.91–40.54	-18.52–20.69
PACS	Median (IQR)	8.7 (-4.55–26.09)	0 (-18.75–8.33)	-1.425≠	0.154	NS
	Range	-33.33–157.14	-37.5–87.5
E wave	Median (IQR)	5.26 (-12.86–15.15)	-3.51 (-15.71–5.45)	-1.136≠	0.256	NS
	Range	-26.58–30	-36.11–20.45
A wave	Median (IQR)	0 (-9.46–9.86)	1.33 (-3.9–3.03)	-0.035≠	0.972	NS
	Range	-98.72–37.29	-11.84–7.46
e'	Median (IQR)	0 (-9.09–14.29)	0 (-14.29–12.5)	-0.942≠	0.346	NS
	Range	-45.45–66.67	-27.27–33.33
E/e'	Median (IQR)	-2.27 (-16.38–5.88)	-9.49 (-15.02–3.06)	-0.996≠	0.319	NS
	Range	-35–43.33	-43.33–42.77
E/A	Median (IQR)	-1.18 (-11.54–5.75)	14.93 (-13.64–17.54)	-0.785≠	0.433	NS
	Range	-27.36–37.25	-35.11–22.58
Maximum Volume	Median (IQR)	0 (-17.24–11.11)	-13.16 (-20.69 – -2.17)	-1.699≠	0.089	NS
	Range	-36.36–80	-32.08–33.33
Minimum Volume	Median (IQR)	0 (-26.67–33.33)	-16.67 (-35.71 – -6.25)	-1.800≠	0.072	NS
	Range	-81.82–228.57	-44.44–53.33
LASI	Median (IQR)	-8 (-17.39–5)	-15 (-30.3–0)	-1.771≠	0.076	NS
	Range	-32.14–35	-37.5–0
P-value > 0.05: Non significant; P-value < 0.05: Significant; P-value < 0.01: Highly significant ≠: Mann-Whitney test

Hypertension (HTN) is a heterogeneous multifactorial disorder. It is a major health problem throughout the world because of its high prevalence and its association with increased risk of cardiovascular disease. Inadequate diagnosis, decreased orientation, and suboptimal control of (BP) in diagnosed patients are a major driver of cardiovascular morbidity and mortality with an increased burden to health care resources.

Patients with hypertension are at risk of structural and functional changes in the LA.(7) There are only a few studies delineating the impact of hypertension on LA function, especially in hypertensive patients with a normal LA size. We, therefore, designed this study to evaluate LA function in patients with a normal or mild increased LA size via deformation imaging. In recent years, strain rate imaging (SRI) has been shown to be an accurate method for quantifying regional myocardial function independent of cardiac rotation and tethering effect. Meanwhile, a few studies have focused on quantifying LA function in hypertensive patients.(8)

Left atrial functional parameters and Systemic arterial hypertension:

Few studies were done to find the correlation between properly controlled hypertension and left atrium functional analysis, Hypertension is associated with LA enlargement and impaired function. Yet the alteration of LA function starts early before changes in left atrial diameters becomes evident. The early detection of subclinical LA dysfunction is of great importance because it is possible to preserve LA reservoir function in hypertensive patients without dilated LA. [8]

In this study we tried to detect early LA dysfunction in properly controlled hypertensive patients and we meant by early that it’s before marked structural changes in LA size represented in LA volume. We used 2D speckle tracking echocardiography for estimation of LA function. Also, we tried to find a correlation between different risk factors and parameters found in hypertensive patients and LA function (strain).

Regarding peak atrial longitudinal strain (PALS):

In the current study, PALS was improved in hypertensive group at the 6 months follow up controlled on medications compared to the base line. PALS showed increase with change of the mean from 35.04 ± 4.33 to 38.92 ± 5.52with P-value 0.001.

This was in concordance with the results of Taamallah K et 2021 In the hypertensive group, with values of 31.23 ± 9.93 in hypertensive group versus 46.43 ± 11.06 in the control group(p = 0.000).(9)

This was in concordance with the study done in 2020 by Ahmet Anil Sahin et al which was done in 30 hypertensive patients and follow up done after 12 weeks of blood pressure control showed increase LA reservoir strain (%) mean at base line (31.4 ± 8.8) then mean after 12 weeks (34.7 ± 9.6) with a P-value 0.020.(10)

Regarding peak atrial contraction strain (PACS):

In the current study, PACS was improved in hypertensive group at the 6 months follow up controlled on medications compared to the base line. PACS showed increase with change of the mean from 17.38 ± 4.67 to 20.46 ± 4.39 with P-value 0.001

This was in discordance with the study done in 2021 by Taamallah K et al, which showed there was no significant difference between the two Groups : hypertensive and non-hypertensive regarding Peak strain, with a value of 16.73 ± 3.84% versus 15.29 ± 2.75% (p = 0.07).(9)

E/e' and arterial hypertension:

In the current study short term follow up for 6 months showed significant decrease in E/e' with change of the mean from 8.8 ± 0.93 to 7.8 ± 1.16 with P-value 0.001.

This is in concordance with Daniel et al in 2021 which showed the frequency of an E/e′ ratio > 14 was reduced from 38 patients (13.3%) to 3.6% (p < 0.001) in medium to long term follow up with mean of 5 years.(11)

Left atrial stiffness index (LASI) and arterial hypertension:

In our study short term follow up after 6 months of proper controlled arterial hypertension showed significant decrease of LASI .LASI showed decrease with change of the mean from 0.24 ± 0.04 to 0.2 ± 0.03with P-value 0.000.This is in concordance with Qiaobing Sun et al in 2021 which showed Left atrial stiffness index was significantly higher in non-dippers [0.29 (0.21, 0.41)] than in dippers [0.26 (0.21, 0.33)] (P < 0.05).(12)

Type of medications and Echocardiography parameters

In our study, Different types of drugs showed no statistical significant difference between type of the drug and changes in echocardiography parameters after 6 months of proper blood pressure control below 140/90 mmHg. This is in concordance with with Degirmenci et al. (2014) it showed no significant difference between patients on irbesartan and patients on nebivolol .(13) This finding points out the importance of ABP control over the choice of medication.

Age and Echocardiography parameters

In our study the only significance was in E and A waves were higher in age groups 50 and higher with P-value 0.002 for the E wave and 0.001 for the A wave. In concordance with our study in 2021 Daniel et al. study showed E and A waves were higher in age group above 55.(11)

IMITATIONS

Single center enrolment.
Relatively small number of patients.
Short term follow up of the patients.
Gold standard was to do ambulatory blood pressure monitoring (ABPM).

Summary

What’s already Known:

An increase in left atrial (LA) size in patients with arterial hypertension has long been known to be associated with worse cardiovascular morbidity and mortality.
Increased left atrial volume and remodeling is associated with various complications, including atrial arrhythmia, stroke, and heart failure.
Transthoracic echocardiography allows new approaches for LA anatomical and functional analysis such as LA stiffness index (LASI) calculation based on LA global longitudinal strain (GLS)

What does this study add:

Our purpose is to standardize a non-invasive method to assess left atrial parameters and utilize these parameters for risk stratifying patients with arterial hypertension and assess response to adequate BP control.
In our current study we included 50 consecutive patients with established systemic arterial hypertension attending Ain-Shams university outpatient clinics, global PALS, PACS, E/e’ and LASI were improved in hypertensive group at the 6 months follow up controlled on medication compared to the base line.
And these results showed that controlling of blood pressure has positive correlation with improvement of left atrial functions.
Our results were almost concordant with previous observations in most of values and act as a supportive study to further utilize 2D echo speckle tracking as a standard protocol to follow up uncontrolled high risk hypertensive patients.

The current study demonstrated that speckle tracking imaging could be used to detect subtle impairment of LA function in patients with hypertension.
Proper control of blood pressure in hypertensive patients lead to improvement in left atrial strain parameters (PALS, PACS, E/e' and LASI).
The clinical usefulness of LA function by speckle tracking echocardiography in hypertensive patients merits further investigations to better precision of the role of the LA study in the prediction of atrial fibrillation, and the risk of heart failure with preserved ejection fraction.

Disclosure

All authors declare that they have no conflicts of interest.
A fund declaration letter is attached after references

Blanco R, Ambrosio G, Belziti C, Lucas L, Arias A, D’Antonio A, et al. Prognostic value of NT-proBNP, and echocardiographic indices of diastolic function, in hospitalized patients with acute heart failure and preserved left ventricular ejection fraction. Int J Cardiol. 2020;317:111–20.
Bastos L, Al-Khalili F, Back M, Manouras A, Engdahl J, Shahgaldi K. Elevated echocardiographic markers for left atrial stiffness and fibrosis in patients with paroxysmal atrial fibrillation. Eur Heart J Cardiovasc Imaging [Internet]. 2021 Feb 8 [cited 2024 Apr 29];22(Supplement_1). Available from: https://dx.doi.org/10.1093/ehjci/jeaa356.120
Deferm S, Martens P, Verbrugge FH, Bertrand PB, Dauw J, Verhaert D, et al. LA Mechanics in Decompensated Heart Failure: Insights From Strain Echocardiography With Invasive Hemodynamics. Cardiovascular Imaging [Internet]. 2020 May 1 [cited 2024 Apr 29];13(5):1107–15. Available from: https://www.jacc.org/doi/10.1016/j.jcmg.2019.12.008
Inoue K, Khan F, Remme E, …NOEH, 2022 undefined. Determinants of left atrial reservoir and pump strain and use of atrial strain for evaluation of left ventricular filling pressure. academic.oup.comK Inoue, FH Khan, EW Remme, N Ohte, E García-Izquierdo, M Chetrit, V Moñivas-PalomeroEuropean Heart Journal-Cardiovascular Imaging, 2022•academic.oup.com [Internet]. [cited 2024 Apr 29]; Available from: https://academic.oup.com/ehjcimaging/article-abstract/23/1/61/6120376
Raman S V, Columbus M. The Hypertensive Heart. An Integrated Understanding Informed by Imaging. J Am Coll Cardiol. 2010;55(2):91–6.
Mahdavi M, Parsaeian M, Mohajer B, Modirian M, Ahmadi N, Yoosefi M, et al. Insight into blood pressure targets for universal coverage of hypertension services in Iran: The 2017 ACC/AHA versus JNC 8 hypertension guidelines. BMC Public Health [Internet]. 2020 Mar 17 [cited 2024 May 25];20(1):1–9. Available from: https://link.springer.com/articles/10.1186/s12889-020-8450-1
Vianna-Pinton R, Moreno CA, Baxter CM, Lee KS, Tsang TSM, Appleton CP. Two-Dimensional Speckle-Tracking Echocardiography of the Left Atrium: Feasibility and Regional Contraction and Relaxation Differences in Normal Subjects. Journal of the American Society of Echocardiography. 2009;22(3):299–305.
Boyd AC, Eshoo S, Richards DAB, Thomas L. Hypertension accelerates the ‘normal’ aging process with a premature increase in left atrial volume. Journal of the American Society of Hypertension. 2013;7(2):149–56.
Taamallah K, Yaakoubi W, Haggui A, Hajlaoui N, Fehri W. Early detection of left atrial dysfunction in hypertensive patients: Role of Speckle Tracking imaging. Tunis Med [Internet]. 2022 Nov 1 [cited 2024 Apr 29];100(11):788–99. Available from: https://europepmc.org/article/med/37551521
Sahin AA, Ozben B, Sunbul M, Yagci I, Sayar N, Cincin A, et al. The effect of cardiac rehabilitation on blood pressure, and on left atrial and ventricular functions in hypertensive patients. Journal of Clinical Ultrasound [Internet]. 2021 Jun 1 [cited 2024 Apr 29];49(5):456–65. Available from: https://onlinelibrary.wiley.com/doi/full/10.1002/jcu.22956
Piskorz D, Keller L, Citta L, Mata L, Citta N, Bongarzoni L, et al. Medium to Long Term Follow-Up of Treated Hypertensive Mediated Heart Disease. High Blood Pressure and Cardiovascular Prevention. 2021 Jul 1 [cited 2024 Apr 29];28(4):383–91. Available from: https://link.springer.com/article/10.1007/s40292-021-00457-7
Sun Q, Pan Y, Zhao Y, Liu Y, Jiang Y. Association of Nighttime Systolic Blood Pressure With Left Atrial-Left Ventricular–Arterial Coupling in Hypertension. Front Cardiovasc Med. 2022;9:814756.
Değirmenci H, Murat Bakirci E. Assessment of effect of irbesartan and nebivolol on the left atrium volume and deformation in the patients with mild-moderate hypertension. 2014 [cited 2024 May 25]; Available from:https://www.researchgate.net/publication/261409320

There is NO conflict of interest to disclose.

Impact of blood pressure control on left atrial diastolic function as determined by 2D speckle tracking echocardiography

Status:

Version 1

Abstract

Aim and Objectives:

Patients and Methods:

Results

Conclusion

Figures

INTRODUCTION

Objective:

Patients and Methods

Type of the Study

Methods

All patients after written informed consent were subjected to the following at baseline:

Two-dimensional (2D) speckle tracking echocardiography (STE):

Follow up data:

Statistical Analysis

RESULTS

Description of the baseline BP and follow up BP after 6 months for the patients:

Description of the demographic data and risk factors among all studied population:

Description of the baseline ECG and Echocardiography parameters for the patients:

Description of the correlation between age, BMI and Echo parameters:

Description between different types of drugs in relation to changes in echocardiography parameters:

DISCUSSION

Left atrial functional parameters and Systemic arterial hypertension:

Regarding peak atrial longitudinal strain (PALS):

Regarding peak atrial contraction strain (PACS):

E/e' and arterial hypertension:

Left atrial stiffness index (LASI) and arterial hypertension:

Type of medications and Echocardiography parameters

Age and Echocardiography parameters

IMITATIONS

Summary

What’s already Known:

What does this study add:

Conclusion

Declarations

References

Additional Declarations

Status:

Version 1