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Cibenzoline is a new antiarrhythmic agent with predominant Vaughan-Williams type 1 properties. The safety, tolerance, and adverse effects of incremental single intravenous doses of this agent were investigated. A total of 28 patients received incremental doses of 0.25 mg/kg (four patients), 0.5 mg/kg (five patients), 0.75 mg/kg (seven patients), 1.0 mg/kg (six patients), or 1.2 mg/kg (six patients) cibenzoline. Another six patients received 2.0 mg/kg disopyramide. Left ventricular function by radionuclide ventriculography and plasma cibenzoline levels were measured at frequent intervals. In the patients who received 1.0 mg/kg and 1.2 mg/kg cibenzoline or patients who received 2.0 mg/kg disopyramide, right and left ventricular filling pressures and cardiac output were measured with a Swan-Ganz catheter. At low-dose cibenzoline (0.25 to 0.75 mg/kg) there was a modest drop in ejection fraction (60% ± 7% to 53% ± 7%). With the higher doses of cibenzoline (1.0 or 1.2 mg/kg) there was a more profound fall in ejection fraction (69% ± 8% to 49% ± 8%) that persisted for approximately 2 hours. This was associated with a rise in end diastolic volume index (74 ± 24 to 85 ± 27 ml/m2) and end systolic volume index (29 ± 15 to 43 ± 18 ml/m2) and a fall in cardiac index (2.65 ± 0.62 to 2.14 ± 0.24 L/min/m2). These hemodynamic changes were similar to those of disopyramide infused at a dose of 2.0 mg/kg: a fall in ejection fraction (57 ± 9 to 48 ± 8), rise in end-end diastolic index (81 ± 44 to 95 ± 55 ml/m2) and end systolic volume index (37 ± 22 to 49 ± 26 ml/m2), and a fall in cardiac index (2.51 ± 0.15 to 2.13 ± 0.16 L/min/m2) and stroke volume (39 ± 8 or 30 ±4 ml/m2). After intravenous infusion, cibenzoline results in significant dose-related negative inotropic effects. An infusion of 1.0 to 1.2 mg/kg results in a similar decline in left ventricular function as does disopyramide infused at a dose of 2.0 mg/kg. Clinical Pharmacology and Therapeutics (1987) 41, 537–545; doi:10.1038/clpt.1987.69

The possible value of myocardial imaging with 201thallium as a screening procedure for the detection of latent disease has not been previously shown. Fifty-eight asymptomatic men underwent exercise 201thallium imaging together with a risk score profile based on the Framingham criteria for predicting future coronary events. Six subjects (10%) developed perfusion defects compatible with myocardial ischemia. The risk score for the population with an abnormal test was 7.7 +/- 2.9%, compared to 2.0 +/- 2.2% (p less than 0.001) for those men with normal tests. Three of the subjects with abnormal scans underwent selective coronary arteriograms; all three had normal coronary arteries. During a 30-month follow-up, all individuals remained physically active and free of cardiac symptoms. Exercise myocardial imaging is not a cost-effective means of detecting coronary artery disease in an asymptomatic population and should not be used as a screening procedure.

The contribution of a liaison psychiatrist to a cardiac transplant programme is described. Ninety one patients were referred to the transplant unit for assessment over four years, and of these, 86 were assessed by the psychiatrist. A high prevalence of preoperative anxiety and depression was found. Thirty four transplants were performed on 33 patients during the study and 22 patients survived. Six patients developed transient delirious episodes during the first 10 postoperative days, three showed symptoms of considerable anxiety, and three developed social and behavioural problems during the convalescent period. Subjects with higher scores on the somatic scale of the general health questionnaire showed increased postoperative mortality. In conclusion, the liaison psychiatrist is useful in evaluating and managing heart transplant patients before and after operation.

Six left atrial myxomas were detected at one hospital in a 15-month period. These tumours are not as rare as was once thought and they frequently cause systemic problems. The diagnosis may easily be missed, but echocardiography is a simple way of establishing the diagnosis. Excision of the tumour usually results in marked symptomatic improvement.

In a 14-month period mitral leaflet prolapse was diagnosed in 85 patients by echocardiography or cineangiography. Chest pain alone was the presenting complaint in 30 patients and linked with palpitation, dyspnoea, or syncope in 9. Eleven presented with major neurological disturbances (9 had transient ischaemic attacks), 10 with palpitation, 4 with undue and persistent fatigue, 2 with dyspnoea, and 2 with dizziness. Seventeen were referred not because of symptoms but because of clicks and murmurs. Overall, chest pain affected 61 patients and unless associated with coronary artery disease was not anginal. Palpitation was admitted by 42 patients; dizziness, lightheadedness, or paraesthesiae by 15, and syncope by 12. Systolic auscultatory abnormalities were noted in 69: 25 had single clicks, 3 had multiple clicks, 19 had both click(s) and murmur, and 22 had a murmur alone. Electrocardiography revealed ST segments flat for greater than 0-10 s in 21, prolonged QTc in 18, and T wave flattening or inversion in inferior limb and lateral chest leads in 14. The exercise stress test was abnormal in 13 of 27 patients. Mitral valve echograms showed definite mitral leaflet prolapse in 61, 'possible' prolapse in 14, and were normal in 8 patients with angiographic proof of mitral leaflet prolapse. Cardiac catheterization with left ventriculography showed prolapse of posterior mitral leaflet in 36, of both leaflets in 2, and left ventricular wall motion abnormalities in 16 cases. Selective coronary arteriography in 31 cases showed major vessel narrowing of larger than or equal to 80 per cent lumen diameter in 4, all with angina. This consecutive series indicates that the physical event of mitral leaflet prolapse is more common than hitherto appreciated, is priminently associated with non-anginal chest pain, palpitation, and neurological disturbances, and in 90 per cent of cases could be shown echocardiographically.

The efficacy of gated synchronous acquisition (GSA) after cardiac blood pool labelling in assessing left ventricular function (ejection fraction and regional wall motion) was evaluated in 31 patients within 24 hours of contrast left ventricular angiography. With the R-wave of the electrocardiogram as a physiologic marker, radionuclide data recorded into an on-line computer allowed construction of cardiac blood pool images during sequential periods of the cardiac cycle. The images, of high count density, have good spatial resolution and can be viewed repetitively in real time in a cine mode. The ejection fractions calculated from the left ventricular time-activity curves corrected for background activity correlated well with the ejection fractions determined from dimension analysis of the contrast left ventricular angiograms (r = 0.87). The results were highly reproducible (r = 0.97). Results of analysis of left ventricular wall motion were similar with the two types of angiograms in 26 of the 31 subjects. GSA is a simple, safe means of evaluating left ventricular ejection fraction and regional wall motion noninvasively.

The efficacy of two beta-receptor antagonists, propranolol and pindolol, was compared with that of a calcium antagonist, verapamil, in the treatment of exertional angina pectoris in 22 men (mean age 51 years). The clinical response and left ventricular function were evaluated with treadmill exercise and with radionuclide ventriculography performed while the patient was at rest or exercising supine with a bicycle ergometer. All the treatments significantly prolonged exercise duration (p less than 0.001) and reduced the number of patients terminating treadmill exercise because of angina (p less than 0.05). The resting heart rate was decreased markedly (p less than 0.001) by propranolol but only slightly (p less than 0.05) by pindolol and verapamil. The left ventricular ejection fraction during rest was unchanged by any treatment, but that during exercise was improved (p less than 0.05) by all the treatments. Patients who failed to gain relief from angina with one of the drugs often responded to another, and adverse reactions occurring with one drug did not necessarily occur with another. In summary, pindolol and verapamil were safe and effective alternatives to propranolol in the treatment of the exertional angina pectoris of these patients.

Between May 1980 and April 1981 four patients were referred to one hospital with syncope or recurrent ventricular fibrillation while taking antiarrhythmic or phenothiazine drugs. In all the patients ventricular tachyarrhythmias with the characteristics of torsades de pointes were documented in association with prolonged QT intervals. With removal of the offending agent (in all the patients) supplemented by temporary overdrive pacing (in two patients) the tachyarrhythmias subsided. This study suggests that drug-induced torsades de pointes is an important clinical entity that occurs more frequently than has been suspected.