Intravascular stenting following bypass grafting in terminal coronary artery disease.

Reoperation after coronary artery bypass grafting in terminal coronary artery disease is associated with a substantial risk. Advances in coronary artery angioplasty offer alternative treatment with low morbidity and acceptable mortality.

Comparison of intravenous nicardipine and nitroglycerin to control systemic hypertension after coronary artery bypass grafting.

The efficacy of intravenous (i.v.) nicardipine hydrochloride (a calcium antagonist) compared with nitroglycerin, the drug generally used for treatment of hypertension after coronary artery bypass grafting, was tested in 20 postoperative patients. The patients were randomly divided in a nonblinded manner into 2 groups. Baseline characteristics were similar in the 2 groups. Patients in both groups received various oral calcium antagonists. In addition, 1 group was treated with i.v. nitroglycerin. Both drugs were infused at a maximal rate of 30 mg/hour, as needed to maintain systolic blood pressure below 110 mm Hg. If blood pressure increased to more than 120 mm Hg, nitroprusside was administered. Intravenous nicardipine was superior to nitroglycerin in control of hypertension after coronary artery bypass grafting. In patients treated with nicardipine, blood pressure was decreased sooner (mean infusion time 7.7 hours vs 11.9 hours for nitroglycerin), mean systolic blood pressure was reduced (94 vs 108 mm Hg for the nitroglycerin group; p less than 0.05), and no patient required nitroprusside treatment (compared with 3 patients who required this treatment in the nitroglycerin group). There were no differences in heart rate, diastolic pressure, cardiac index and urine flow between the 2 treatment groups. No adverse effects were observed in patients treated with nicardipine.

Accelerated progression of coronary artery disease.

Atheromatous disease of the arteries is progressive and often results in untimely morbidity and premature death. The pathogenesis of the arterial lesion is as complex as its rate of progression is variable and ill understood. In six patients undergoing coronary arteriography, who were being restudied before percutaneous transluminal coronary angioplasty, the angiographic appearance deteriorated considerably over a fairly short period (mean 3.6 months). Although early detection and preventive measures have lowered the incidence of atheromatous disease and improved survival in some patients, rapid progression of the disease remains a serious hazard in others, who, as a group, remain at present unidentifiable.

Incidence and prevention of supraventricular tachyarrhythmias after coronary bypass surgery.

Supraventricular tachyarrhythmias are a frequent complication encountered after coronary artery bypass grafting. A retrospective survey of 102 consecutive patients undergoing exclusive bypass grafting at St. Mary's Hospital supplemented by a review of 16 published reports over a period of 10 years revealed a mean incidence of post-operative tachyarrhythmia of 33.4% in 1344 patients (range 11.4-100%). One hundred and thirty two patients undergoing exclusive bypass surgery, were randomised prospectively in double blind fashion to receive either oral timolol or matched placebo approximately 24 hours after surgery. In the 66 patients receiving timolol, there was a significant reduction of post-operative arrhythmias compared to the 66 patients receiving placebo: from 19.7 to 7.5% (P less than 0.05). Of all arrhythmias, two thirds appeared under 48 hours after surgery. In the timolol group, 4 patients developed systemic hypotension. This was readily reversed by withdrawing the drug. No other side effects were noted. The use of oral timolol after coronary artery surgery significantly lowers the incidence of post-operative supraventricular arrhythmias.

The value of exercise-induced U-wave inversion on ECG chest wall mapping in the identification of individual coronary arterial lesions.

Exercise-induced U-wave inversion on chest wall mapping was compared with coronary arteriographic findings in 160 consecutive patients who presented with chest pain suggestive of ischaemic heart disease. ECG recordings were made from 16 points on the chest wall before, during and after exercise. None of the 27 patients with normal coronary arteriograms developed U-wave inversion during or after exercise (specificity = 100%). In 21 (all males) of the 133 patients (15.8%) with significant coronary arterial lesions, U-wave inversion on exercise was noticed on different coronary artery territories on the chest wall map, and its localization was correlated with angiographic evidence of individual coronary arterial lesions (100% projection rate). In 9 patients (6.8%) this sign was observed in the absence of any ST segment changes or Q waves. Exercise-induced U-wave inversion was the sole ECG criterion reflecting a lesion of the left anterior descending artery in 12 cases (9%), of the circumflex in 6 cases (4.5%), and in only one case of right coronary artery disease. This sign was not detectable in the conventional V5 site in 9 cases (7.1%) with significant disease of the left anterior descending coronary artery. These nine patients showed U-wave inversion on other areas of the left anterior descending coronary artery territory on exercise. Exercise-induced U-wave inversion disappeared in all the ten patients who underwent coronary artery bypass graft surgery. It is suggested that exercise-induced U-wave inversion shown on chest wall mapping is a reliable indicator of coronary artery disease, which disappears after myocardial revascularization, and in addition, aids identification of individual coronary arterial lesions.

Electrocardiographic chest wall mapping in the diagnosis of coronary artery disease.

Chest wall mapping of ST segment changes, inverted U waves, and Q waves using 16 electrocardiographic electrodes was performed at rest and during and after bicycle ergometry in 150 patients presenting with chest pain suggestive of angina. All patients underwent coronary angiography. The presence or absence of appreciable coronary artery disease (greater than or equal to 50% stenosis) was detected with a sensitivity of 98% and a specificity of 88%. The identification of lesions in individual coronary arteries was also possible with a sensitivity and specificity of 87% and 85% respectively for the territory of the left anterior descending and diagonal artery, 71% and 85% respectively for the right coronary artery, and 85% and 80% respectively for the circumflex artery. This test appears to be a reliable non-invasive screening method for selecting patients for angiography.

Dissection of the aorta.

Dissection of the aorta is not an uncommon condition, nor is it as lethal as was previously considered. The correct diagnosis and ensuing management depend as much on the index of suspicion of the attending doctor as on the prompt planning of noninvasive and invasive investigations. Most patients can be treated conservatively in the initial stages by means of appropriate hypotensive pharmaceutical agents. Surgery offers a better chance of survival for proximal dissection, whereas long-term medical management is indicated in the distal dissection in the absence of severe complications.

Acute dissection of the aorta: long-term review and management.

A review of 50 cases of acute dissection of the aorta managed over a period of almost 15 years showed that patients with either proximal or complex dissections had a better prognosis when managed surgically, whereas medical treatment offered a better change of survival in patients with distal dissection. Angiography was generally safe and reliable, most cases being correctly diagnosed by this means. The majority of patients can be managed conservatively in the initial stages.

Uhl's anomaly.

Uhl's anomaly of the heart is a rare condition. Another well-documented case is presented with a review of the published reports outlining the main clinical features and the bad overall prognosis. Right atriotomy should be avoided if closure of the atrial septal defect is attempted.

Plasma noradrenaline concentrations during isometric exercise.

Blood was collected simultaneously from the left ventricle and pulmonary artery in 12 patients undergoing routine cardiac catheterisation and was analysed for noradrenaline concentrations at rest, during, and after isometric stress (hand grip). Moderate isometric exercise resulted in a significant rise in plasma noradrenaline with a return to basal values 10 minutes after discontinuing the grip test. There were no significant differences in noradrenaline levels between the left ventricular and pulmonary arterial samples either at rest or during exercise. Three patients with evident left ventricular dysfunction had the highest plasma noradrenaline concentrations, in contrast to the much lower levels in 2 patients on beta-blockers and in 1 patient with a normal heart. As moderate isometric effort results in an important increase in noradrenaline level, this form of exercise could be dangerous in subjects suffering from ischaemic heart disease or in those with impaired left ventricular function since these patients are particularly susceptible to arrhythmias.

Left ventricular apical thin point.

The wall thickness of the apex of the left ventricle has been measured at its thinnest point in 60 adult hearts at necropsy. This measured 2 mm or less in 97% of them and 1 mm or less in 67%.

Fatal outcome arising from use of a sutureless "corkscrew" epicardial pacing electrode inserted into apex of left ventricle.

A 59-year-old man is described in whom the insertion of an epicardial sutureless "corkscrew" electrode resulted in fatal ventricular perforation. Fatal myocardial perforation can occur with this electrode and the apex of the left ventricle should never be used as the site of insertion. Necropsy also showed that the transvenous right ventricular electrode, inserted one year previously, had penetrated a tricuspid leaflet. This could have accounted for the ensuing pacing failure.

The grip test: a simple method for the assessment of left ventricular performance.

37 patients with mixed cardiac pathologies were subjected to isometric exercise (hand grip) during routine cardiac catheterization. On the basis of a simple and safe grip test it was possible to distinguish three groups of patients according to the left ventricular pressure at rest and its response to this test. Group 1 consisted of 14 patients with left ventricular end diastolic pressures remaining below 12 mm Hg both at rest and on exercise. These patients were considered to have normal left ventricular function some, even in the presence of organic heart disease. No deaths occurred in this group during the follow-up period which averaged 33.8 months. At the other extreme (Group 3) there were 12 obviously disabled patients with resting left ventricular filling pressures above 12 mm Hg rising further under isometric stress. Six of these patients (50%) died during the period of the study. (Average follow-up 21.4 months). By the application of the hand grip test, an intermediate population (Group 2) of 11 patients was discernible. These patients were able to maintain a normal cardiac reserve at rest (LVEDP less than 12 mm Hg) but not during isometric effort (LVEDP greater than 12 mm Hg). Two of these patients (18%) died during the follow up period (average 22.1 months). Assuming a pathological progression with time from groups 1-3 and in view of the different prognoses observed in the course of the long-term follow-up it would appear that the Group 2 patients should be considered more critically and offered more active management.