Analysis of Differences in Assessment of Left Ventricular Function on Echocardiography and Nuclear Perfusion Imaging

Prognostic value of the left ventricular ejection fraction reserve acquired by gated myocardial perfusion SPECT in patients with CAD and reduced stress LVEF

Purpose

Left ventricular ejection fraction (LVEF) strongly predicts cardiac events. However, conflicting findings exist regarding the prognostic value of the LVEF reserve (ΔLVEF) when measured by gated single-photon emission computed tomography myocardial perfusion imaging (SPECT G-MPI). In particular, data related to the prognostic value of ΔLVEF when measured by SPECT in patients with reduced LVEF are scarce. In this study, we aimed to evaluate the prognostic value of ΔLVEF when acquired by SPECT G-MPI in patients with coronary artery disease (CAD) and a LVEFStress < 60%.

Methods

We retrospectively recruited 260 consecutive patients diagnosed with CAD by coronary angiography (CAG) and a LVEFStress < 60%, as determined by SPECT G-MPI. These patients were followed up for 33.4 ± 7.6 months. The patients were divided into two groups (ΔLVEF > 0% and ΔLVEF ≤ 0%), and survival analyses were conducted. The primary endpoints were major adverse cardiac events (MACEs), a composite of all-cause death, nonfatal myocardial infarction, unplanned coronary revascularization, and hospitalization for unstable angina.

Results

We observed 69 MACEs (26.5%). The cumulative incidence of MACEs in patients with ΔLVEF ≤ 0% was significantly higher than in patients with ΔLVEF > 0% (P = 0.042). Multivariate Cox regression further revealed that a ΔLVEF ≤ 0% represented an independent predictor of MACEs (adjusted hazard ratio [HR]: 1.276; 95% confidence interval [CI]: (1.006, 1.618), P = 0.045). Adding a ΔLVEF ≤ 0% to traditional myocardial perfusion and function variables evaluated by MPI significantly improved the ability to predict MACEs (P = 0.044).

Conclusions

Determining ΔLVEF by SPECT G-MPI was associated with MACEs and improved risk stratification compared to prediction models based on traditional perfusion and functional parameters in CAD patients with left ventricular dysfunction, particularly those with no or mild myocardial ischemia.

Diagnostic Value of Echocardiography Combined with Serum h-FABP and cTnI in Myocardial Infarction and Its Evaluation Value in Left Ventricular Function

Objective

To explore the value of color Doppler echocardiography (CDE) combined with serum heart-type fatty acid-binding protein (h-FABP) and cardiac troponin I (cTnI) in the diagnosis of myocardial infarction and its evaluation value in left ventricular function.

Methods

A total of 44 patients with myocardial infarction who were treated in Cangzhou Central Hospital from October 2018 to February 2020 were included in the observation group, and 45 healthy subjects were included in the control group. The serum h-FABP and cTnI levels of the two groups were compared and analyzed. The coincidence rate of echocardiography plus serum h-FABP and cTnI for single diagnosis and combined diagnosis was analyzed. The left ventricular function indexes of patients with myocardial infarction in different cardiac function grades were compared, including left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), stroke volume (SV), cardiac index (CI), and the ratio of peak velocity blood flow from left ventricular relaxation in early diastole to peak velocity flow in late diastole (E/A). The value of echocardiography combined with serum h-FABP and cTnI in the left ventricular function in patients with myocardial infarction was analyzed.

Results

The levels of serum h-FABP and cTnI in the observation group were significantly higher than those in the control group (P < 0.05). CDE plus serum h-FABP and cTnI was associated with significantly higher sensitivity, specificity, and accuracy in diagnosing myocardial infarction versus single detection (P < 0.05). The LVEDV, SV, and CI parameters were similar in patients with different cardiac function grades (P > 0.05). Compared with cardiac function grades I and II, the level of LVEF in patients with myocardial infarction in grades III and IV of cardiac function decreased, while the levels of LVEDD, LVESD, LVESV, and E/A increased (P < 0.05). The levels of serum h-FABP and cTnI in patients with myocardial infarction increased with the increase of cardiac function grades (P < 0.05).

Conclusion

Patients with myocardial infarction show high levels of h-FABP and cTnI, and CDE plus the detection of serum h-FABP and cTnI levels can significantly improve the detection accuracy and effectively evaluate the left ventricular function of patients with myocardial infarction, with a certain predictive value for cardiac function grading in myocardial infarction.