Lessons from reporting 100, 000 Jamaican electrocardiograms

The screening programme of the Heart Foundation of Jamaica has found hypertension in 71 percent of women and 47 percent of men. Of these patients, 13 percent were newly discovered hypertensives. Left ventricular hyperthrophy was present in 18 percent of hypertensive women and 27 percent of men. Inadequate control of raised blood pressure was a frequent finding. Ischaemic electrocardiographic (ECG) changes were only found in 4 percent of the 14,739 patients seen in the past two years but this is an underestimation of the prevalence of ischaemic heart disease. Arrhythmias seen over 15 years were usually benign, of sinus origin or ectopics in the absence of heart disease. Uncontrolled atrial fibrillation remains the most serious arrhythmia encountered and usually in hypertensive patients. Obesity found in 80 percent of women is a problem requiring public education. `Silent' ischaemia in diabetic and left ventricular hypertrophy indicate the need for ECG examination in all newly diagnosed patients with either condition, and annual ECGs thereafter. (AU)

Cardiac fibroma presenting as sudden death in a six-month-old infant

Cardiac fibroma is a rare benign tumour which occurs predominantly in infancy and childhood. We present the case of a six-month-old female infant who died suddenly at home and was found at autopsy to have a large cardiac fibroma in the ventricular septum. The tumor was apparently asymptomatic although there was evidence of mild cardiac failure. Death was thought to be due to a fatal arrhythmia. (Au)

Ambulatory electrocardiography in Jamaica: the early experience

This study reports the early experience with ambulatory electrocardiography in Jamaica. Fifty patients were subjected to ambulatory electrocardiographic monitoring with a low-cost, battery-powered intermittent recorder (incorporating patient activation capability). The duration of monitoring was usually approximately 24 hours, and playback analysis of the electrocardiograms was effected through a simple single-channel electrocardiograph machine. The majority of patients (56 percent) were in the 41-70 year age group, and only 12 percent were over 70 years of age; 60 percent were monitored because of palpitations, 16 percent because of presyncope or syncope or syncope, and 14 percent because of chest pain. Sixteen patients (32 percent) activated the monitor to report symptoms, and in 81 percent of these (13 patients), the cardiac rhythm remained sinus; paroxysmal supraventricular arrhythmias were documented in the other 3 patients. Asymptomatic arrhythmias detected included supraventricular premature contractions (24 percent), premature ventricular contractions (16 percent) - including complex post-infarction ectopy - sinus arrhythmia (6 percent), and 2nd degree Mobitz II atrio-ventricular block (2 percent). On the basis of the above results, the following conclusions appear justified: 1) ambulatory electrocardiography using an intermittent recorder and simple playback system is feasible and has the great advantage - for the Caribbean - of its low cost and hence greater potential availability, and 2) clear cut clinically useful information can be obtained using this technique (AU)

Twenty four hour ambulatory electrocardiography "Holter Monitoring" in the assessment and management of arrhythmias - abstract

Thirty patients suspected of having cardiac arrhythmias were subjected to Holter monitoring to assist in documentation and symptom-diary correlation. The system consists of a 400 gm weight Schillings 2000 two-channel recorder connected to chest electrodes. The patients carried on with their usual daily activities. The tapes were scanned, using an Avionics Model 660 Dynamic Electroscanner. There were twenty male and ten female patients. Eight (26 percent) were under 29 years, eleven (37 percent) and eleven (37 percent) were between ages 30-49 years and 50-70 years respectively. Twenty-eight patients had symptoms varying from troublesome palpitations to near syncope. Of these, eighteen (60 percent) showed significant Holter abnormality. Nine positives (32 percent) were in fourteen patients with repeated normal resting E.C.G.'s. Abnormalties included paroxysmal supraventricular tachycardia, atrial flutter/fibrillation, singus bradycardia, sinus bradycardia, sinus tachycardia and frequent premature ventricular contractions. Nine positive reports (32 percent) were also documented in the other fourteen symptomatic patients who had shown a resting E.C.G. abnormality. These included marked ventricular irritability, bradycardiatachycardia, sinus delay and arrest, and second degree A-V block. Two asymptomatic persons were assessed, one after transient post-myocardial infarction (3§A-V block) and another with hypertrophic cardiomyopathy. Both showed normal records. Four studies documented adequate antiarrhythmic medical suppression of previously documented severe ventricular irritability. Holter monitoring is a convenient and effecient means of documenting the presence or absence of suspected cardiac arrhythmias in symptomatic patients. It is helpful in assessing malignant arrhythmia in high-risk situations and after initiating antiarrhythmic therapy. It is especially helpful in preventing "blind" therapy and in reasuring younger patients who often have benign sinus and supraventricular arrhythmias (AU)

Rate and rhythm changes in the heart during intubation of the trachea

A prospective study done on 45 Jamaican patients is presented. The effects of either using or avoiding atropine premedication, and the spraying of the larynx with 4 per cent lignocaine and/or intravenous propanolol prior to the induction agent, on the heart rate and rhythm are described. The findings demonstrate a significant increase in the heart rate during laryngoscopy and intubation in all groups of patients and neither lignocaine nor propanolol afford any appreciable protection against increase in heart rate. However, both these agents completely eliminate the incidence of the intubation arrhythmias (AU)

The role of echocardiography in the selection of mitral valve prosthesis

Assessment of the left ventricular outflow tract was made echographically in 70 patients who subsequently received a mitral prosthesis. Group A (44 patients) had normal left ventricular outflow tract width (>20 mm.); 13 received the Starr-Edwards prosthesis and nine received the Braunwald-Cutter prothesis. There were two patients with low cardiac output syndrome and no hospital deaths. Group B (26 patients) had a narrow left ventricular outflow tract (<20 mm.). Thirteen patients received the Starr-Edwards prosthesis. One patient had low cardiac output syndrome, and there were no hospital deaths. We conclude that the use of the ball-and-cage prosthesis in the mitral position in patients with a narrowed left ventricular outflow tract (<20 mm.) measured echographically is not associated with an increased surgical risk. (Summary)

Pre-excitation at the University Hospital of the West Indies - abstract

The aim of this study was to assess the overall prevalence of pre-excitation syndromes and correlate their clinical association with refractory and life-threatening arrhythmias. All electrocardiograms (ECGs) taken at the University Hospital of the West Indies (UWHI) between January and December, 1979 were analyzed for pre-excitation syndromes. Pertinent clinical data were extracted from hospital records. A total of 6,332 ECGs were reviewed. Fifty-two patients (ages 5 to 83 years) with pre-excitation were detected (8 per 1,000). Of these, 43 had the typical delta waves with variable PR intervals and QRS complexes, while 9 had short PR with normal QRS. These syndromes were associated with a broad spectrum of clinical entities, both cardiac and non-cardiac. The majority of patients were free of dysrhythmias (62 per cent), with pre-excitation being an incidental electrocardiographic (ECG) finding. Twenty patients (38 per cent) had significant arrhythmias, the majority of which were supraventricular. In some, these arrhythmias required frequent hospitalizations or clinic visits. At times, the arrhythmias were refractory to drug therapy and responded only to electrical cardioversion. Two of these patients (4 per cent of the series) died in refractory ventricular tachycardia and fibrillation. Both patients had associated Barlow Syndrome. Pre-excitation is not a rare entity in Jamaica. It appears to be a benign incidental ECG finding in the majority of patients seen at UHWI. However, when it is found in patients with the Barlow Syndrome, rheumatic fever and rheumatic heart disease, sickle cell disease with cardiomegaly and infection or renal failure, congestive cardiomyopathy, congenital heart disease and thyrotoxicosis, it can lead to potentially life-threatening arrhythmias. We recommend therefore that careful cardiac assessment be performed in all patients with ECG diagnosis of pre-excitation to detect those patients at high risk of dying suddenly (AU)

The incidence and management of life-threatening arrhythmias occurring during the course of acute myocardial infarction - abstract

During the last decade the early detection and successful treatment of life-treatening arrhythmias have resulted in a significant reduction in the mortality rate of patients with myocardial infarction. The purpose of this study was to determine the incidence of these dangerous arrhythmias and to explore the possibility of producing a similar reduction in mortality rate with our limited resources. Since the 1st July, 1971, all patients with clinical diagnosis of acute myocardial infarction have been admitted to a coronary bed in either the intensive care unit or one of our general medical wards. Each be is fully equipped with a cardioscope for the continual monitoring of the patient's electrocardiogram, a defibrillator/cardioverter and the necessary anti-arrhythmic drugs and resuscitative equipment. During the first 7 months of this project a total of 24 patients with unequivocal evidence of myocardial infarction were admitted to the study and their rhythm was continually monitored for period varying from at least 48 hours up to 21 days. Four patients died from cardiogenic shock and in addition 2 of these patients had bronchopneumonia. Nine of the 24 patients showed a significant rhythm change (40 percent) and of these, 5 patients (20 percent) had a life-threatening arrhythmia. These included (a) fast atrial fibrillation, (b) sinus bradycardia with Stokes-Adams attacks, (c) complete heart block with Strokes-Adams attack, (d) ventricular tachycardia and (e) ventricular fibrillation were treated with a combination of practolol and digoxin with cardioversion being reserved for resistant cases. Sinus bradycardia was treated with frequent doses of atropine (0.6 mgm. I.M. 2 to 6 hourly) and complete heart block was controlled by transvenous endocardial pacing. Lignocaine was used as the drug of choice for ventricular tachycardia and so far there have been no cases of ventricular tachycardia which have been resistant to this drug. Ventricular fibrillation was treated with immediate defibrillation starting at an energy level of 300 Watts Seconds. It is concluded that serious arrhythmias do occur in at least 20 percent of our patients with acute myocardial infarction and we have demonstrated that these can be successfully treated here (AU)

The arrhythmias in consulting practice - abstract

An investigation was made of the incidence and aetiology of the arrhythmias in a private consulting practice. The case histories and ECGs of all cases referred for a cardiac consultation in the last six years were examined. Of 1,800 cases, 575 cases had normal ECG's, 774 had abnormalities of the ECG other than arrhythmias and 451 presented arrhythmias of whom 36 showed more than one type. The arrhythmias were as follows - Sinus tachycardia 135 cases, Sinus bradycardia 5, Sinus arrhythmia 29, sinus arrest 1, coronary sinus rhythm 1, supra-ventricular premature beats 46, ventricular premature beats 118, paroxysmal atrial tachycardia 3, paroxysmal ventricular tachycardia 1, atrial flutter 5, flutter fibrillation 8, Atrial fibrillation 37, Sino-auricular block 1, atrio-ventricular block 42, right bundle branch block 40 left bundle branch block 11, Wolff-Parkinson-White syndrome 5. Approximately 20 percent of the arrhythmias were due to ischaemic heart disease and of all the cases of ischaemic heart disease seen, approximately 20 percent showed an arrhythmia. Of 29 cases of sinus arrhythmia 21 were older than 15 and 14 older than 20. 4.4 percent of cases of sinus tachycardia were due to alcoholism. In both the group of ventricular premature beats and the group of supra-ventricular premature beats about 1/3 showed no other evidence of heart disease and about 1/4 showed evidence of ischaemic heart disease. On of the five cases of atrial flutter and one of the eight cases of flutter fibrillation had artificial mitral valves. Of six cases of acquired heart block, the youngest was 59 years of age (AU)