28 patients (12 men and 16 women) with the paroxysmal AF were studied, who were planned for the radiofrequency PVI. Generally, AF progressed in patients with coronary artery disease (64%) and with essential hypertension (61%).
CHF of FC I– III by the NYHA (New York Heart Association) classification was diagnosed in 19 patients according to the clinical diagnosis based on the medical history; namely, 2 patients had FC I; 12 patients had FC II; 5 patients had FC III.
The duration of AF in the first group was 7.00 ± 2.28 years, the duration of arterial hypertension was 20.75 ± 4.88 years. In addition to the primary therapy, 9 patients had diuretic medication: mineralocorticoid receptor antagonists (MCRA) and indapamide. In 4 patients torasemide in a dose of 2.5 to 5 mg was prescribed. Table 1 presents a total characteristic of the patients.
Table 1
The characteristic of the patients
Parameter
|
Patients with AF and CHF (n = 19)
|
Patients with AF without CHF (n = 9)
|
Control values
(n = 44)
|
Gender (male)
|
6 (31.6%)
|
6 (66.7%)ˆ
|
26 (38.6%)
|
Age (years)
|
61.72 ± 3.66ˆ
|
55.83 ± 6.62ˆ
|
35.02 ± 2.44
|
Coronary artery disease: effort of exertion
|
15*
|
3
|
|
Arterial hypertension
|
14
|
8
|
|
Postinfarction cardiosclerosis
|
|
1
|
|
Acute stroke in the past
|
3
|
0
|
|
Dilated cardiomyopathy
|
2
|
0
|
|
Type 2 diabetes
|
2
|
1
|
|
Paroxysmal AF
|
19
|
9
|
|
Duration of AF, years
|
7.00 ± 2.28*
|
3.60 ± 1.80
|
|
Duration of hypertension, years
|
20.75 ± 4.88*
|
9.43 ± 3.98
|
|
CHF (functional class):
|
|
|
|
FC I
|
2
|
0
|
|
FC II
|
12*
|
0
|
|
FC III
|
5*
|
0
|
|
Obesity
|
8
|
4
|
|
Therapy: Beta– adrenoblockers
|
7
|
2
|
|
ACEI/ARB
|
10*/9*
|
1
|
|
MCRA/indapamide and hydrochlorothiazide/torasemide
|
4/5*/4
|
0/0/0
|
|
Calcium antagonists
|
3
|
0
|
|
Statins
|
11
|
3
|
|
Antiarrhythmic therapy
|
13
|
3
|
|
Note: ACEI/ARB is the angiotensin converting enzyme inhibitors/ angiotensin receptor blockers. MCRA is the mineralocorticoid receptor antagonists. * indicates the significance of the differences between groups of patients, p < 0.05. ˆ indicates the significance of differences between groups of patient and control group, p < 0.05. |
AF duration in the second group was 3.60 ± 1.80 years, the duration of arterial hypertension was 9.43 ± 3.98 years. Patients in this group received the basic therapy without diuretic medication.
Patients from the control group were significantly younger than in the examined one. We were not able to find practically healthy people at the same age as the patients from the examined groups.
Patients with AF with and without CHF, as compared to the control group, according to echocardiography, had the dilatation of the left atrium (LAVI) (67.70 ± 1.91 ml.; 68.00 ± 3.17 ml. and 49.29 ± 4.33 ml., respectively, Table 2), the maximum diameter of RSPV (22.39 ± 0.95 mm.; 21.44 ± 1.67 mm. and 13.50 ± 0.44 mm., respectively, Images 1 A, 2A, 3A) and the minimum diameter of RSPV (11.78 ± 1.19 mm.; 11.33 ± 1.29 mm., and 6.42 ± 0.17 mm., respectively, Images 1B, 2B, 3B); the average Е/e' was the same in both groups (patients with AF with and without CHF); it was 8.92 ± 0.73 and 8.62 ± 1.31, respectively. This indicates that values of the average Е/e' are in the grey zone and require additional investigation in order to clarify the presence or absence of hypertension in the left atrium [10]. For the patients with AF, with and without CHF, the calculated wedge pressure is significantly higher than that of the control group, but lower than 12, i.e. it is within the range of reference values [19].
Table 2
Echocardiographic and invasive parameters of hemodynamics
Parameter
|
Control values
(n = 44)
|
Patients with AF and CHF (n = 19)
|
Р
|
Patients with AF without CHF (n = 9)
|
Р
|
Р′
|
LAVI, ml
|
49.29 ± 4.33
|
50.25 ± 7.65
|
< 0,001
|
40.26 ± 3.17
|
< 0,001
|
0,80
|
Simpson's ejection fraction, %
|
62.89 ± 1.47
|
58.63 ± 6.79
|
0,75
|
65.5 ± 2.66
|
0,80
|
0,18
|
Transmitral E/A
|
1.61 ± 0.07
|
0.77 ± 0.05
|
< 0,001
|
0.75 ± 0.08
|
< 0,001
|
0,7
|
Septal е'
|
13.25 ± 0.63
|
7.03 ± 0.74
|
< 0,001
|
6.88 ± 0.79
|
< 0,001
|
0,85
|
LV lateral е'
|
17.85 ± 0.94
|
10.03 ± 0.87
|
< 0,001
|
10.62 ± 1.94
|
< 0,001
|
0,48
|
Average Е/e'
|
6.83 ± 0.29
|
8.92 ± 0.73
|
< 0,001
|
8.62 ± 1.31
|
< 0,001
|
0,70
|
Calculated PAWP, mm Hg
|
1.97 ± 0.004
|
11.48 ± 1.04
|
< 0,001
|
10.82 ± 1.64
|
< 0,001
|
0,49
|
Maximum pulmonary vein diameter, mm
|
13.50 ± 0.44
|
22.39 ± 0.95
|
< 0,001
|
21.44 ± 1.67
|
< 0,001
|
0,25
|
Minimum pulmonary vein diameter, mm
|
6.42 ± 0.17
|
11.78 ± 1.19
|
< 0,001
|
11.33 ± 1.29
|
< 0,001
|
0,90
|
Invasively measured pressure in the LA, mm Hg
|
2– 12 (7.9) [19]
|
14.68 ± 1.40
|
|
15.00 ± 2.63
|
|
0,85
|
PASP, mm Hg
|
15.23 ± 1.24
|
36.11 ± 4.64
|
< 0,001
|
29.33 ± 3.28
|
< 0,001
|
0,18
|
Transtricuspid E/A
|
1.58 ± 0.07
|
0.82 ± 0.04
|
< 0,001
|
0.91 ± 0.12
|
< 0,001
|
0,06
|
RV lateral е'
|
15.00 ± 0.82
|
8.73 ± 0.83
|
< 0,001
|
8.30 ± 1.12
|
< 0,001
|
0,60
|
IVC, cm
|
17.60 ± 0.76
|
22.41 ± 1.35
|
< 0,001
|
21.89 ± 2.40
|
< 0,001
|
0,70
|
Calculated RAP, mm Hg
|
3.68 ± 0.24
|
10.36 ± 0.81
|
< 0,001
|
11.57 ± 2.55
|
< 0,001
|
0,20
|
Invasively measured pressure in the RA, mm Hg
|
1– 7 (3.9) [19]
|
6.75 ± 0.63
|
|
6.13 ± 1.13
|
< 0,001
|
0,29
|
Note: LAVI is the left atrial indexed volume, E/A is the ratio of the blood flow velocity in the phase of early diastolic ventricular filling to the filling velocity in the late atrial filling phase; average Е/е' is the ratio of the early– diastolic blood flow velocity to the velocity of the lateral part and the medial part of the fibrous annulus of the mitral valve; PCWP is the pulmonary capillary wedge pressure; PASP is the pulmonary artery systolic pressure; IVC is the inferior vena cava; RAP – right atrial pressure. P indicates the significance of the differences between each group of patients and the control group. Р′ indicates the significance of the differences between groups of patients. |
Table 3
Correlation of invasively measured pressure in the left atrium with echocardiographic parameters
Parameter
|
Invasively measured pressure in the LA, mm Hg
|
Invasively measured pressure in the RA, mm Hg
|
LA volume, ml
|
– 0,12
|
|
Average Е/e'
|
– 0,29
|
|
Calculated PAWP, mm Hg
|
– 0,11
|
|
Maximum pulmonary vein diameter, mm
|
– 0,06
|
|
Minimum pulmonary vein diameter, mm
|
0,65*
|
|
PASP, mm Hg
|
0,21
|
0,54
|
IVC, cm
|
|
0,49*
|
Calculated RAP, mm Hg
|
|
0,16
|
Note: * – statistically significant correlation, p < 0.05 |
Thus, according to the existing ultrasound methods for the congestion detection in the pulmonary circulation, patients with the paroxysmal AF, regardless of CHF diagnosed by cardiologists, had no venous pulmonary hypertension. However, the invasively measured pressure in LA was found to be elevated both in the group of patients with AF and CHF (14.68 ± 1.40 mm Hg) and in the group with AF and without CHF (15.00 ± 2.63 mm Hg). This shows the presence of the venous pulmonary hypertension and CHF in patients of both groups.
There was an average positive correlation between the minimum diameter of right superior pulmonary vein and invasive mean pressure in the left atrium (r = 0.65, p < 0.05). There was not a correlation between the maximum diameters of the right superior pulmonary vein and invasive mean pressure in the left atrium (r =-0.06, statistically insignificant). There was not a correlation between the average Е/e' and invasive mean pressure in the left atrium (r =-0.29, statistically insignificant).
ROC analysis was performed to verify the reliability of the ultrasound diagnostics model of the venous pulmonary hypertension by the maximum and minimum diameters of the right superior pulmonary vein. For the maximum diameter of the pulmonary vein, AUC = 0.599 (p < 0.05), which indicates that this model has an average degree of quality. The equilibrium point is the value of the maximum diameter of RSPV– 21.7 mm, which corresponds to the limit of the norm (sensitivity– 75%, specificity– 86%).
For the minimum diameter of the pulmonary vein, AUC = 0.613 (p < 0.05), which indicates that this model has an average degree of quality. The equilibrium point is the minimum diameter of RSPV– 10.5 mm, which corresponds to the limit of the norm (sensitivity– 85%, specificity– 86%).
Thus, the method for determining venous pulmonary hypertension by measuring the maximum and/or minimum diameters of the pulmonary vein can be effectively used as the noninvasive diagnostics of the venous congestion in the pulmonary circulation.
For the patients AF with and without CHF, the calculated pressure in RA was 10.36 ± 0.81 and 11.57 ± 2.55 mm Hg, respectively; under the invasive measurement method it was, respectively, 6.75 ± 0.63 and 6.13 ± 1.13 mm Hg. This indicates that the pressure calculated echocardiographically is overrated.
There was a positive correlation between invasive measured mean pressure in RA and IVC diameter on exhalation (r = 0.49, p < 0.05).
For the maximum diameter of the IVC obtained the following graph ROC curve with AUC = 0.832 (p < 0.05), indicating that this model has a very good degree of quality. The equilibrium point is the value of the diameter of the IVC – 18.5, which corresponds to the limit of the norm (sensitivity – 100%, specificity – 92%).