Predictors of mortality in patients with left ventricular failure [abstract]

We retrospectively reviewed the clinical presentation and five-year mortality of 64 consecutive adults who underwent echocardiography at the Eric Williams Medical Sciences Complex between January 1992 and December 1994 with a left ventricular ejection fraction < 40 percent. The mean age was 60ñ12 years and 68 percent of patients were male. The prevalence of diabetes mellitus and hypertension was 40 percent and 46 percent, respectively. The mean left ventricle ejection fraction was 30ñ9 percent. The most common primary cost of left ventricular failure was coronary artery disease (CAD) in 47 percent, idiopathic dilated cardiomyopathy (9 percent), hypertensive heart disease (9 percent), alcohol related dilated cardiomyopathy (8 percent) and valvular heart disease (6 percent). Angiotensin converting enzyme inhibitors were prescribed in 85 percent of cases, diuretics (82 percent), digoxin (61 percent), warfarin (18 percent), beta blockers (10 percent), and amiodarone (8 percent). Survival data were available for 84 percent. Mortality was 53 percent at 5 years. Independent predictors of mortality were age, the use of beta blockers and left ventricular internal diameter. In conclusion, CAD was the most common cause of left ventricular failure. Five-year mortality was high, particularly in elderly patients with marked ventricular dilatation. (AU)

The feasibility of a porcine model of acute coronary occlusion and reperfusion using off-pump coronary artery bypass grafting

We developed an open-chest porcine model of acute coronary occlusion and surgical reperfusion, and attempted to prevent intra-operative ischaemic ventricular fibrillation (VF) by a Retrograde Intracoronary Glyceryl trinitrate (RIG) infusion into the occluded vessel. Five Yorkshire pigs (weight 50ñ 1.1kg), randomized into 3 groups, underwent median sternotomy under general anaesthesia. One pig (Group 1, control) underwent sternotomy and pericardiotomy only. Four pigs underwent acute left anterior descending (LAD) coronary occlusion. Two pigs were not reperfused (Group 2). Two pigs underwent surgical reperfusion (Group 3) via left internal mammary artery (LIMA) grafting to the LAD using the Off-Pump Coronary Artery Bypass (OPCAB) technique. Ischaemic injury was assessed using 7-lead electrocardiography (EGG) and transthoracic/epimyocardial echocardiography (ECHO). Group 1: transient intraoperative hypotension and VF occurred. Successful resuscitation and 10-week survival (until sacrifice) with normal left ventricular (LV) function was achieved. Group 2: there were ECG and ECHO evidence of acute LV ischaemic dysfunction in both pigs. The surviving pig had persistent anterior hypokinesis at 8« months. The other died intra-operatively following progressive ischaemic LV dysfunction despite resuscitative attempts. Group 3: the surving pig had normal LV function at 8 months. Initial anterior LV akinesis normalized within 7 days. The other developed post-occlusion haemodynamic instability and died intra-operatively despite reperfusion. In this porcine model, acute LAD artery occlusion modified by the novel RIG infusion technique, followed by surgical reperfusion (OPCAB) is feasible. This model would facilitate further development of OPCAB surgical expertise and understanding of the pathophysiology of ischaemia-reperfusion injury.(Au)

Systolic left ventricular dysfunction detected by echocardiography: demographics and aetiology - abstract

The aim of this retrospective study was to determine the demographic features and causes of heart failure in patients presenting a tertiary care institution: 65 patients aged >16 years with an ejection fraction (EF) < 40 percent, undergoing echocardiography during a two-year period, 1992-94, were included in the study. The mean age was 60 ñ 12 years, 68 percent were male, 50 percent and 42 percent were African and East Indian, respectively. The prevalence of diabetes and hypertension was 40 percent and 45.3 percent respectively. The majority of patients were in NYHA class II or III. The mean left ventricular ejection fraction (LVEF) was 29.7 ñ 8.6 percent. There was no correlation between NYHA class and LVEF at initial presentation. The underlying causes of heart failure were coronary artery disease (CAD) (42 percent), idiopathic dilated cardiomyopathy (10.9 percent), hypertensive heart disease (9.4 percent), alcohol related dilated cardiomyopathy (7.8 percent), valvular heart disease (7.8 percent), myocarditis (1.6 percent) and hypertrophic cardiomyopathy (1.6 percent). The dominant primary cause could not be determined in 18.8 percent. LVEF was similarly depressed in the two major ethnic groups and in the ischaemic and non-ischemic cardiomyopathy groups. We concluded that CAD was the most common cause of LV systolic dsyfunction and that LVEF was not related to ethnicity, aetiology or severity of symptoms. (AU)