Paediatric open heart surgery in Trinidad and Tobago: an example of collaborative care / Cirugía Pediátrica a Corazón Abierto en Trinidad y Tobago

Between September 1998 and February 2003, 204 children underwent cardiac surgery in Trinidad and Tobago to correct or palliate congenital heart disease. The defects included isolated ventricular or atrial septal defects as well as tetralogy of fallot and coarctation of the aorta. A few patients also had complex cyanotic congenital heart disease. The patients ranged in age from 2 days to 17 years. In some cases, palliative surgery was undertaken as a first step towards complete correction but the majority of patients underwent complete repair. The commonest postoperative complications were haemorrhage and small transient pericardial effusions. The overall mortality rate was < 1. This paper describes the cardiac lesions, post-operative morbidity and mortality of these patients

Entre septiembre de 1998 y febrero de 2003, 204 niños fueron sometidos a cirugía cardíaca en Trinidad y Tobago, a fin de corregir o paliar la enfermedad cardíaca congénita. Las cardiopatías incluían defectos septales atriales o venticulares aislados, así como tetralogía de Fallot y coartación de la aorta. Algunos pacientes también presentaban cardiopatía congénita cianótica compleja. Los pacientes tenían edades que fluctuaban de dos días a 17 años. En algunos casos, la cirugía paliativa se emprendió como un primer paso hacia la corrección completa pero a la mayoría de los pacientes se les practicó la reparación completa. Las complicaciones más comunes del post-operatorio fueron hemorragias y pequeñas efusiones pericadiales transitorias. La tasa general de mortalidad fue <1%. Este trabajo describe las lesiones cardíacas, la morbilidad y mortalidad post-operatoria de estos pacientes.

Provision of anaesthesia for porcine cardiac transplantation at the veterinary school in Trinidad and Tobago

A successful heterotopic cardiac transplantation was performed between sibling female Yorkshire Juvenile swine. Adequate pre-medication with azaperone and a smooth induction were ensured for both pigs, which were anaesthetized simultaneously with sodium thiopentone followed by endotracheal intubation and intermittent positive pressure ventilation. Inhalation anaesthetic agents were used for maintenance, neuromuscular blockade was achieved with cisatracurium and both fentanyl and tramadol were used to provide analgesia. Invasive monitoring was used in both the donor and recipient. Central venous pressure (CVP) was maintained at > 10 cm H2O and mean arterial pressure (MAP) > 60 mmHg. Heparin was injected during the surgical dissection of the heart in the donor to prevent coronary thrombosis and prior to aortic side clamping for end-to-side anastomosis of the donor heart in the recipient abdomen. After transplantation, the cardiovascular parameters of the recipient showed a MAP of 85-105 mmHg and a CVP of 8-10 cm H2O while echocardiography of the transplanted heart confirmed an ejection fraction (EF) of 80. A functional anaesthetic team was assembled and trained to provide anaesthesia for porcine cardiac transplantation. The transplanted heart suffered pump failure after 69 days and was excised for performance of tissue analysis

The initial Trinidad experience with Cine MRI in clinical cardiology

We describe the initial Trinidad experience with Magnetic Resonance Imaging (MRI) and Cine MRI as a diagnostic tool in clinical cardiology. Six patients from the following categories were referred for Cine MRI evaluation: congenital heart disease, valvular heart disease, aortic diseases, cardiomyopathy and intracardiac mass. All patients underwent echocardiography. MRI and Cine MRI were performed on all patients using a Siemens Magnetom 1.0 Tesla MR system at MRI Trinidad and Tobago Ltd. Selected patients underwent Angiography and/or computed tomography (CT) scanning. Clinical data and images of the six patients evaluated are described. MRI and Cine MRI provided excellent anatomical and functional details of the heart and aorta in five patients with dissection of the aorta, aneurysm of the ascending aorta, suspected left ventricular apical thrombus, infiltrative cardiomyopathy and arrhythmogenic right ventricular dysplasia. Technical difficulty was experienced with one patient who had a congenital defect (common atrium). In this study, Cine MRI provided excellent images in all but one patient. This new noninvasive technique enhanced diagnostic capabilities and facilitated management in patients with certain cardiovascular diseases.

Coronary artery bypass graft outcome: the Trinidad and Tobago experience

The study is retrospective review of the demographic, clinical, angiographic, and operative data of the first 205 consecutive CABG operations performed by Caribbean Heart Care at the Eric Williams Medical Sciences Complex (EWMSC), Trinidad and Tobago, between November 1993 and December 1997. The aim of the study was to determine the in-hospital and intermediate-term follow-up results. The mean age of patients was 59 +/- 10 years and 78 were male. Sixty-four per cent were of East Indian descent, whereas 16 were of African descent. Forty-eight per cent of the patients were hypertensive, 46 were diabetic, 33 had hyperlipidaemia, 20 had a recent history of cigarette smoking and 16 were obese. Sixty-five per cent had a positive family history of ischaemic heart disease. The average time interval between angiography and surgery was 2.3 months. At the time of angiography, 63.5 of patients had Canadian Cardiac Society (CCS) class 3 or 4 angina. The mean ejection fraction was 61 +/- 15. Wall motion abnormalities were seen in 67 of patients. Significant stenoses of the left anterior descending artery, right circumflex artery, circumflex and ramus coronary arteries were present in 91, 78, 54 and 5, respectively. Many patients (67) had severe diffuse disease on angiography. The mean intensive care stay was 2.2 +/- 0.8 days. In-hospital mortality was 3.9 (8/205). The most frequent post-operative complication was haemorrhage (2.6). Acute renal failure occurred in 2.1; pulmonary collapse, 1.6; stroke, 1 and cardiac arrest, 1. Both sternal wound infections and systemic sepsis occurred in 0.5. Intermediate-term follow-up data were obtained for 92 (189/205). The duration of follow-up ranged from 1 to 5 years (mean 3.7 years). During the follow-up period, 7 patients (3.4) died. Angina severity was reduced from a mean CCS score of 2.61 +/- 0.95 before CABG to 1.22 +/- 0.55 at the time of follow-up (p < 0.0001). Overall 4-year mortality compared favourably with data from international studies. Among survivors, quality of life improved as evidenced by the reduction in the mean angina score.

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 50 +/- 1.1 kg), 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 (ECG) 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 1/2 months. The other died intra-operatively following progressive ischaemic LV dysfunction despite resuscitative attempts. Group 3: the surviving 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.