EFFECT OF PRIMARY PERCUTANEOUS CORONARY INTERVENTION ON THE INCIDENCE AND SEVERITY OF ISCHEMIC MITRAL REGURGITATION IN PATIENTS WITH ACUTE ST-ELEVATION MYOCARDIAL INFARCTION.

Background: Ischemic mitral regurgitation (IMR) is mitral incompetence resulting from coronary artery disease in the absence of intrinsic valve lesions. This common complication of acute myocardial infarction (AMI) (1) occurs in 15–64% of patients after this event, (2) and is an independent predictor of future cardiovascular mortality(3). The pathophysiology of ischemic MR is complex, and its presence may be related to several underlying processes that are often difficult to separate in a given patient(4). It may result from altered ventricular geometry(5,6,7), incomplete mitral leaflet coaptation, papillary muscle dysfunction and regional wall motion abnormalities (8). IMR severity is positively associated with development of heart failure after AMI.(9).Because of its complex pathophysiology and heterogeneous clinical presentation, the proper treatment of ischemic MR is often debated, and the relative utility of revascularization with and without concomitant mitral valve surgery is uncertain(4). Although primary percutaneous coronary intervention (PCI) for AMI is known to improve outcome(10,11,12), and that IMR after myocardial infarction (MI) worsens outcome, (13) the effect of primary PCI on IMR incidence has not been specifically studied.
Aim of the work: To detect the impact of Primary PCI on the development and severity of ischemic mitral valve regurgitation in patients presenting with acute ST segment elevation myocardial infarction.
Patients and methods: This study included 60 patients presenting for the first time with Acute ST segment elevation myocardial infarction The patients were divided into two groups group A: Included 30 patients who were treated with primary PCI group B included 30 patients who were treated by thrombolytic therapy..All patients had echocardiography after reperfusion , during the hospital stay then reevaluation after one month period.
Results:. During hospital stay the mean LV EF in the PCI group was 46.17± 7.51 % while in the SK group the mean EF was 41.67±6.06 %.In the PCI group the mean wall motion score index during the hospital stay was 1.25± 0.15 while in the SK group it was 1.39 ±0.14 with P value less than 0.001.At one month follow up. In the PCI group there were 6 patients with mitral regurgitation the mean jet area was (1.33±0.63) cm2, while in the SK group there were 25 patients with mitral regurgitation the mean jet area was( 4.45 ±2.17) cm2 with P value <0.0001In the PCI group the severity of mitral regurge was positively correlated with the age of the patient P value less than 0.01,door to needle P value less than 0.01 and pain to hospital times P value 0.04.In the streptokinase group, the severity of mitral regurgitation was positively correlated with door to needle time delay with P value of 0.03.
Conclusion: Primary PCI decreased the incidence and severity of chronic ischemic mitral regurgitation when compared with medical reperfusion in patients with acute ST segment elevation myocardial infarction.