RESUMO
Background: Cardiac resynchronization therapy (CRT) had shown great promise in improving hospitalization and mortality of the patients suffering from refractory heart failure (HF) inspite of optimal medical management. The goal of CRT is to reduce cardiac mechanical dyssynchrony, thereby enabling the heart to contract more efficiently. Mechanical ventricular dyssynchrony as estimated by electrical dyssynchrony, is assessed with the QRS duration. But electrical and mechanical dyssynchrony are not well correlated in all HF patients. The dyssynchrony might have been related to the underlying etiology of HF. Objective: To compare the concordance of mechanical and electrical dyssynchrony in both ischemic and nonischemic cardiomyopathy patients. Methods: Doppler echocardiography and strain echocardiography was performed in 76 patients presenting with heart failure due to ischemic cardiomyopathy (n=40) or nonischemic cardiomyopathy (n=36) with left ventricular ejection fraction<35% & New York Heart Association class III–IV, regardless of their QRS duration. Interventricular dyssynchrony was assessed by the time interval between preaortic and prepulmonary ejection times. Intra-ventricular dyssynchrony was assessed by using conventional Doppler and strain echocardiograpy. Obtained from the three standard apical view (TMinMax) and (2) the standard deviation of the averaged time-to-peak strain (TPS-SD, ms) and (3) time to peak myocardial systolic velocity (Ts-SD) of same segments. Result: The correlation coefficient between QRS duration and mechanical interventricular dyssynchrony was significant (r=0.57, P=0.001) in patients with non-ischemic cardiomyopathy and insignificant (r=0.175, p=0.281) in patients with ischemic cardiomyoparhy. The correlation coefficient between QRS duration and mechanical intraventricular dyssynchrony was significant in patients with nonischemic cardiomyopathy (r= 0.69, P = 0.001 for TMin Max; r=0.57, P= 0.001 for TPS-SD; r=0.48, p=0.003 for TS-SD) and insignificant in patients with ischemic cardiomyopathy (r=0.153; p=0.345 for TMin Max; r=0.178; p=0.273 for TPS-SD r=0.139; p=0.392 for TS-SD). Conclusion: This study showed that the relationship between electrical and mechanical dyssynchrony is dependent on the underlying etiology of heart failure.
RESUMO
This study was conducted in three tertiary hospitals in Dhaka city at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka Medical College Hospital (DMCH) and National Institute of Cardiovascular Disease (NICVD) as a part of Inter-Heart Study. Secondary data was obtained from the standard questionnaires to determine door to needle time (DNT) following thrombolytic therapy in patients with Acute Myocardial Infarction (AMI) in coronary care units at three large tertiary referral hospitals in Dhaka city. Of total 192 patients studied in three centres, 156 (81.2%) received thrombolytic therapy. In BSMMU, 33 out of 45 (73.33%) patients received thrombolysis. Mean DNT was 147 minutes. Eighteen (55%) patients received thrombolysis within 90 minutes and 9 patients (27%) received with in 91-180 minutes, 6 patients (18%) received thrombolysis after 180 minutes. In DMCH, 44 out of 57 patients (77.1%) received thrombolysis. Mean DNT was 210 minutes. Five patients (11%) received within 90 minutes, 19 (43%) received thrombolysis between 91 to 180 minutes and 20 patients (46%) received thrombolysis outside the range of 180 minutes. In the NICVD, 79 out of total 90 (87.7%) patients received thrombolysis. Mean DTN was 64 minutes. Sixty seven (82%) patients received therapy within 90 minutes, 6 patients (9%) received between thrombolysis 91-180 minutes and 6 (9%) patients received after 180 minutes of reaching hospital. Inspite of overall improvement in the management of patients with AMI in coronary care units of major teaching hospitals, there seem to remain certain difficulty in our system which causes delay in thrombolysing patients with AMI. In this study, the mean DNT for thrombolysis was quickest (64 minutes) at NICVD and slowest (210 minutes) at DMCH. Although the study was conducted almost four years ago, it gives some insight regarding strength and weaknesses in the infrastructure of public sector hospitals in our country.