We retrospectively analyzed the predisposing factors that affect cardiovascular events and mortality in LVT patients, and found that higher BNP levels were associated with increased risk of all-cause mortality.
A previous retrospective review of more than 80,000 medical records revealed that the incidence of LVT is 7 per 10,000 patients . Another observational study identified 128 patients with LV thrombus from 140,636 echocardiograms . Consistent with these reports, the incidence of LVT was also low in our study and only 156 patients were recruited after screening more than 957,000 echocardiographic records. While PCI has markedly reduced the incidence of post-myocardial infarction LVT, cases related to heart failure have increased. Around 2/3rd of the patients in our cohort were diagnosed with CHD and the rest with dilated cardiomyopathy. The etiology of LVT patients evolves. One study showed that 80% of LVT cases are ischemic , and Bhatt et al showed that de novo HF (38%) was more frequently associated with LVT compared to acute MI (25.9%) . This discrepancy may be due to the bias of small LVT population, or the different criteria utilized by the studies to analyze the precipitating factor of LVT.
Despite its low incidence rate, LVT is a lethal complication of MI or HF and is associated with high rates of systemic embolism, morbidity and mortality. We observed 10 cases of systemic embolism during the follow-up, which is similar to the reported 2–3% for PCI. Early revascularization can attenuate left ventricular dysfunction and therefore decrease the risk for LVT and associated embolism. Furthermore, anticoagulation therapy resolves the thrombus and further lowers the SE incidence to 1.9% within a year . In addition, Maniwa et al reported a high incidence (16.3%) of SE in AMI patients with LVT , which can be attributed to the statistical variations in the incidence of LVT, longer follow-up period and lower primary PCI rate.
LVT patients are usually at a very high risk of developing major adverse cardiovascular events (MACE), including embolic or major bleeding complications, as well as death. A retrospective study of 159 LVT patients screened from 90,065 echocardiograms reported that MACE and all-cause mortality occurred in 37.1% and 18.9% of the patients respectively within a median follow-up period of 632 days . Likewise, another study reported in-hospital mortality of 7.8% and post-discharge one-year mortality rate of 13% among LVT patients . In this study, we followed up the patients for 702 days and detected mortality rate of 30.44%. These findings collectively show the poor prognosis of LVT. Although PCI and adjunctive therapy have improved the outcome of LVT, it is crucial to identify the high-risk patients through appropriate predictive markers.
BNP is a diagnostic biomarker of HF, and its high levels are associated with poor prognosis of HF patients. MI frequently leads to ventricular dysfunction and HF, which is accompanied by BNP elevation. In our study as well, BNP was the most potent predicator of all-cause mortality of LVT patients, and elevated BNP correlated to greater risk of death. Anti-coagulation therapy is recommended to LVT patients if not contraindicated according to several guidelines. The current ESC guidelines recommend 6 months as the minimum duration of anticoagulation therapy . However, prolonged anti-coagulation may benefit patients with recurrent and late LVT formation. The outcomes of HF patients have improved markedly in recent years due to drugs that inhibit or even reverse cardiac remodeling. Thus, beta-blockers, angiotensin receptor neprilysin inhibitor (ARNI) and sodium-glucose cotransporter (SGLT)2 inhibitors should be initiated in patients with elevated BNP.
The study has several limitations that ought to be considered. This was a retrospective study conducted on a single center cohort, although a large number of medical records screened. Second, echocardiography was used to diagnose LVT, which might be not be as sensitive or specific as cardiac magnetic resonance imaging for detecting LVT formation. Third, the sample size was small due to the low incidence of LVT, which may have limited identification of other potential risk factors. Finally, the results of this observational study should be considered exploratory rather than definitive.