Prevention of sudden cardiac death in athletes, sportspersons and marathoners in India

The annual incidence of sudden cardiac death (SCD) in athletes is significantly lower than the general population. However, when SCD occurs in an athlete during sporting event or training, it sends shockwaves in the society and raises questions about cardiovascular effects of sports and exercise. This document reviews the causes and mechanism of SCD in sports and exercise in young and older athletes. In the Indian context, we suggest a ‘pre-participation screening’ of young and older athletes and consider a ‘supervised, graded exercise regime’ for the uninitiated, older sports participant. Finally, the document proposes medical infrastructure required to successfully revive a victim of sudden cardiac arrest during a sporting event.

Protein C deficiency leading to pulmonary thromboembolism in a patient with hereditary spherocytosis.

Hereditary protein C deficiency results in a hypercoagulable state that can manifest itself as venous thrombosis and pulmonary embolism. The prevalence of this condition, even among patients with familial thrombosis, is quite low. We report a case of protein C deficiency presenting as massive pulmonary thromboembolism in a patient with hereditary spherocytosis, an uncommon hemolytic disorder not usually associated with increased thrombotic risk. A review of the literature revealed only a few cases of thrombosis associated with hereditary spherocytosis, and none of them had protein C deficiency. This makes the present case the first of its kind to be reported.

Implantation of Dual-Chamber Cardioverter-Defibrillator through Left Iliac Vein in a Patient with Occluded Superior Vena Cava.

The occlusion of the superior vena cava is a known complication of repeated procedures related to pacemaker and implantable cardioverter-defibrillator devices. The insertion of implantable cardioverter-defibrillators in patients with this complication entails the practical problem of how to gain access to the heart. Surgical placement of epicardial leads and patches, using thoracotomy,is an established alternative but has its inherent problems, including high surgical risk. Also, the necessary hardware is not easily available. The existing literature has few reports of the insertion of implantable cardioverter-defibrillators through alternative transvenous routes. We report a case of implantation of a dual-chamber implantable cardioverter-defibrillator through the left iliac vein in a patient with arrhythmogenic right ventricular dysplasia, recurrent ventricular tachycardia and an occluded superior vena cava.

Non-invasive assessment of endothelial function by brachial artery flow mediated vasodilatation and its association with coronary artery disease: an Indian perspective.

Endothelial dysfunction is the final common pathway through which various coronary risk factors culminate into atherosclerosis and subsequent coronary artery disease (CAD). Endothelial function can be reliably assessed by flow mediated vasodilatation (FMD) in the brachial artery using high-resolution ultrasonography and has been shown to be an excellent surrogate marker for the presence of CAD. Two hundred and forty-one individuals comprising of 101 patients with CAD (angiographically proven, or with history of documented myocardial infarction) and 140 individuals without CAD were included in the study. All subjects underwent clinical evaluation, fasting lipid profile, treadmill test and FMD assessment. Selected individuals underwent coronary angiography too. Brachial artery diameter and Doppler indices (systolic and diastolic velocity time integrals) were recorded using high resolution ultrasonography at baseline, immediately after and at one minute after release of cuff (occlusion time 5 minutes). FMD was calculated as percentage increase in brachial artery diameter at one minute. FMD index was calculated as the ratio of FMD and percentage increase in flow during reactive hyperaemia. Mean FMD was significantly higher in non-CAD group (8.71+/-4.77%) than in CAD group (3.77+/-2.03%; p < 0.0001). The FMD index was also significantly higher in the non-CAD group (0.031 ) than in CAD group (0.021; p=0.0117). On multiple regression analysis, FMD index was found to be significantly associated with presence of CAD (p=0.0015), independent of conventional cardiovascular risk factors. Endothelial function as assessed by FMD is significantly depressed in patients with established CAD and this association is independent of presence of conventional cardiovascular risk factors.

Carotid intima-media thickness and brachial-ankle pulse wave velocity in patients with and without coronary artery disease.

BACKGROUND: Carotid intima-media thickness and pulse wave velocity are non-invasive markers of atherosclerosis and have been shown to reliably predict presence and extent of atherosclerotic vascular disease. However, studies examining their association with each other have shown inconsistent results. Hence it was sought to assess correlation between carotid intima-media thickness and pulse wave velocity in patients with and without coronary artery disease. METHODS AND RESULTS: Sixty-four patients with angiographically proven coronary artery disease and 84 age-matched individuals without coronary artery disease but having one or more conventional cardiovascular risk factors were included in the study. Individuals with established cerebrovascular disease and peripheral vascular disease were excluded from the study. Carotid intima-media thickness of far wall was measured at three predefined sites (distal common carotid, carotid bifurcation and proximal internal carotid artery) on each side. Brachial-ankle pulse wave velocity was measured non-invasively using VP 1000 (Colin Corporation) automated ABI/ PWV analyzer. There was no significant difference in gender and presence of cardiovascular risk factors in the two groups. Mean and maximum carotid intima-media thickness and brachial-ankle pulse wave velocity were all significantly higher in coronary artery disease patients as compared to patients without coronary artery disease (0.842 v. ( 0.657 mm, p <0.0001; 1.076 v. 0.795 mm, p <0.0001; 1708.63 v. 1547.26 cm/s, p <0.0004 respectively). There was a significant correlation between brachial-ankle pulse wave velocity and both mean and maximum carotid intima-media thickness in patients with coronary artery disease (r = 0.47, p <0.0001 and r=0.41, p < 0.0008 respectively) but not in individuals without coronary artery disease (r=0.01 and -0.1 respectively). CONCLUSIONS: Presence of significant correlation between carotid intima-media thickness and brachial-ankle pulse wave velocity in patients with coronary artery disease but absence of the same in individuals without major atherosclerotic vascular disease suggests that the correlation between carotid intima-media thickness and brachial-ankle pulse wave velocity becomes stronger with increasing extent of atherosclerosis.