Abnormal inter-ventricular diastolic mechanical delay in patients with ST-segment elevation myocardial infarction

BACKGROUND

This study aimed to investigate the ventricular mechanical relaxation pattern and its clinical influence in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

Echocardiography was performed to measure mitral and tricuspid diastolic opening times. Left ventricular diastolic mechanical delay (LVMDd) was defined as diastolic filling of the right ventricle earlier than that of the left ventricle, and right ventricular diastolic mechanical delay (RVMDd) was defined as the right ventricular diastolic filling later than left ventricular filling.

RESULTS

Among 152 patients with STEMI, 100 (65.8%) had LVMDd, and 47 (30.9%) had RVMDd. In-hospital complications were significantly increased in patients with RVMDd (61.6% vs. 41.0%, P = 0.017). Those with RVMDd exhibited significantly lower left ventricular global longitudinal strain (11.7 ± 4.1% vs. 13.2 ± 4.0%, P = 0.035), global work index (913.8 ± 365.9 vs. 1098.9 ± 358.8 mmHg%, P = 0.005) and global constructive work (1218.6 ± 392.8 vs. 1393.7 ± 432.7 mmHg%, P = 0.021). Mitral deceleration time significantly decreased (127.4 ± 33.5 vs. 145.6 ± 41.7 ms, P = 0.012), and the ratio of early mitral inflow to early mitral annular velocity (E/E') significantly increased [13.0(11.0-20.0) vs. 11.9(9.3-14.3), P = 0.006] in the RVMDd group. Logistic regression analysis showed that age (odds ratio [OR]:0.920; P = 0.001), brain natriuretic peptide level (OR: 1.1002; P = 0.036) and mitral E/E' (OR: 1.187; P = 0.003) were independently associated with RVMDd.

CONCLUSIONS

Delayed right ventricular filling is related to more severe left ventricular systolic and diastolic dysfunction in STEMI patients. More attention should be paid to patients with RVMDd to prevent adverse events during hospitalization.

Usefulness of echocardiographic myocardial work in evaluating the microvascular perfusion in STEMI patients after revascularization

Background

Left ventricular myocardial work (MW) assessed by echocardiography has recently been introduced as a new index of global and regional myocardial performance. The presence of microvascular obstruction after revascularization in ST-segment elevation myocardial infarction (STEMI) patients predicts poor clinical outcomes. This study aimed to explore the usefulness of MW in identifying impaired microvascular perfusion (MVP) in the patients with STEMI after revascularization.

Methods

One hundred and sixty STEMI patients who underwent myocardial contrast echocardiography (MCE) within 48 h after percutaneous coronary intervention (PCI) were included. Patients were divided into normal MVP and impaired MVP groups according to the myocardial perfusion score. The clinical data, coronary angiography results and echocardiographic data including Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were collected.

Results

Impaired MVP was found in 60% of patients. Compared with the normal MVP group, GWI (909.2 ± 287.6 mmHg% vs. 1191.2 ± 378.2 mmHg%), GCW (1198.3 ± 339.6 mmHg% vs. 1525.9 ± 420.5 mmHg%), GWE (82.7 ± 7.8% vs. 86.8 ± 5.6%) and GLS (− 11.0 ± 3.4% vs. − 14.4 ± 3.8%) were significantly reduced in the impaired MVP group. Whereas there was no statistically significant difference in left ventricular ejection fraction (LVEF) and GWW, multivariate logistic regression analysis showed that peak troponin I (OR 1.017, 95% CI 1.006–1.029; P = 0.004), final TIMI flow ≤ 2 (OR 16.366, 95% CI 1.998–134.06; P = 0.009), left ventricular end-diastolic volume index (LVEDVi) (OR 1.139 95% CI 1.048–1.239; P = 0.002), and GWI (OR 0.997 95% CI 0.994–1.000; P = 0.029) were independently associated with impaired MVP. GWI showed a good sensitivity (86.8%) but low specificity (53.7%) in identifying impaired MVP (AUC 0.712, 95% CI 0.620–0.804; P < 0.001). Combination with GWI can improve the diagnostic value of TNI or LVEVi for impaired MVP.

Conclusion

Impaired MVP is relatively common in STEMI patients after revascularization and independently associated with left ventricular GWI assessed by echocardiography. GWI confer incremental value to MVP assessment in STEMI patients.

Takotsubo cardiomyopathy associated with bronchoscopic operation: A case report

BACKGROUND

Takotsubo cardiomyopathy (TTC), a syndrome of acute left ventricular (LV) dysfunction, is characterized by transitory hypokinesis of LV apices with compensatory hyperkinesis of the LV basal region. The symptoms of TTC mimic acute myocardial infarction, without significant coronary stenoses on coronary angiography. Echocardiogram plays a key role in the diagnosis and prognosis of TTC. New indicators from echocardiograms may be helpful in disease evaluation.

CASE SUMMARY

A 67-year-old man with a 10-year history of non-small cell lung cancer was admitted to our hospital for emerging facial edema and dry cough. Bronchoscopic lavage, brushing, and biopsy were performed to evaluate tumor progression. During this procedure, he complained of left chest pain, nausea, and vomiting, with elevated troponin levels. Electrocardiogram showed sinus bradycardia with ST-segment elevation in I, AVL, and V4 to V6 leads. Coronary angiography revealed mild stenosis in the right coronary artery. Echocardiography showed hypokinesis of LV apices with compensatory hyperkinesis of the LV basal region. At the 7-d follow-up, echocardiographic pressure-strain analysis showed a normal LV ejection fraction, but partial recovery of LV myocardial work, which fully recovered 5 mo later.

CONCLUSION

This is a case of TTC caused by bronchoscopic operation. We strongly recommend noninvasive myocardial work measured by echocardiographic pressure-strain analysis as a necessary supplementary test for the long-term follow-up of TTC.