Ethnocultural heart: another challenge for an emerging diversity.

Race, ethnic origin and culture, as well as other aspects of diversity, affect cardiovascular care. This is relevant to Canada with its ever-increasing diversity. The dynamic interplay of genetic, biological and environmental influences leads to differences and variability. Understanding the role of these determinants leads to the challenge of reducing or eliminating differences in cardiovascular care related to diversity.

Chaos in medicine and health care: an idea whose time has come - abstract

The world is at the edge of chaos and taking science and medicine with it. There is a new perspective in the understanding of nature (including science and medicine) with elements of holism, dynamic interaction, interrelatedness, variability and unpredictability, away from the rigid deterministic clockwork universe on Newton. This new science of Chaos and Complexity (the edge of chaos) based on the mathematics and physics of non-linearity offers a more realistic model to understand our non-linear world. Our perspective and teaching of medicine will change to include chaos and the emergent interactions of complexity. The science of Chaos and Complexity has widespread implications for all aspects of medicine. Different more realistic models can now be used to look at health care delivery, epidemiology of disease, the variability of clinical expression of disease and molecular biology and variable genetic expression. The mathematics and physics of chaos explains the intrinsic unpredictability and variability that exists in biological systems, yielding a more reasonable understanding of the expected and unexpected in clinical and research medicine. Chaos in the coronary is an example of this dynamic interrelatedness, interactions and sensitive dependence on initial conditions that lead to progression or regression towards an acute coronary syndrome or myocardial infarction (AU)

Myocardial infarction at 30, 25 and even 20 years of age: chaos in prevention and prevention in order - abstract

A 20-year-old patient develops myocardial infarction (MI) after playing hockey, with another acute event at the age of 30 years despite normal coronary arteries. A 25-year-old non-smoker awakes with chest pain and major anterior MI. A 35-year-old develops stress-induced, threatened major anterior MI. A 45-year-old patient with stable, mild coronary artery disease at catheterization develops MI after a dispute. Patients develop acute coronary syndromes unexpectedly and unpredictably. A few patients with risk factors and a few young patients with few or no usual risk factors developing acute coronary events are presented. Such events may lead an already sceptical public to the notion of futility in risk modification or chaos in prevention. Chaos and Complexity, a new science based on mathematics and physics of nonlinear systems as most of medicine is, offers a model for understanding unexpected events in clinical medicine. Unpredictability is inherent because of the interrelatedness of local and distant events and sensitive dependence on initial conditions where small causes lead to huge effects, and thus variable clinical outcomes. Understanding chaos, complexity and the newer concepts of pathogenesis and acute risk factors should keep prevention, despite unpredictability

Multicultural paediatrics ... Toronto 1993: the new reality - abstract

The new reality of practising paediatrics in Toronto, 1993, is recognition of the city's great ethnic and cultural diversity. The multicultural mix of initial European immigrants and the later influx from the Caribbean, S.E. Asia, Hong Kong, India, Pakistan, Sri Lanka, Africa, South America, the Middle East, Eastern Europe and the former Eastern Block, creates challenges to the practice of medicine and paediatrics. We are now faced with a new medicine - of unusual diseases, homeopathy and herbal medicines of many cultures and of differing concepts of child care and discipline. Language difficulties and distortion from nuances of language, traditional and cultural expectations, adaptation, assimilation and cultural changes, all produce tremendous pressures on children and family. Specifically, the cultural and religious diversity of the new immigrants with differing views on childbirth, child rearing, nutrition

ECG Abnormality, T-inversion V2 to 4 on ECG, indicative of high grade LAD stenosis and high risk of progression to myocardial infarction - abstract

Patients with unstable angina may progress rapidly to further myocardial infarction. A typical ECG pattern, inversion of the T-wave in V2 to V4 on the surface ECG, has been reported to predict high grade LAD stenosis and early progression to anterior myocardial infarction. (C. de Zwaan et al, American Heart Journal, Volume 117, Number 3, Pages 657 to 665, March 1989). Although published, this is not common knowledge among family doctors, specialists or cardiologists. We have had experience with over one hundred patients with this abnormality and our experience is similar. A few illustrative cases are presented to show the clinical picture, typical ECG abnormality of so-called terminal T-wave inversion in the V-leads, heart cath correlation, and progress. 1. Patients with acute coronary syndromes, and inversion of the terminal portion of the T-wave on ECG, V2 to V4, are high risk for progression to major anterior MI by virtue of high grade LAD lesion. 2. At heart cath a small number of these patients demonstrate normal arteries with presumed spasm, or plaque rupture and thrombus. 3. These patients constitute a subset of patients with non-Q-wave MI and should be treated differently. 4. These patients may develop a transient normal ECG with chest pain or with stress test. 5. A very small number will have this abnormality as a chronic change for other reasons (AU)

Stress-induced sudden death or ischaemia - abstract

A few cases of acute coronary syndrome precipitated by stress are described. A 34-year-old female survived seventeen minutes of ventricular fibrillation and CPR, threatened anterior myocardial infarction, LV dysfunction, with normal coronary arteries and normal LV function later demonstrated. This was entirely emotional stress induced. A 45-year-old patient developed severe ischaemia (marked ST elevation on ECG, and angina), with the stress of venipuncture and was later shown to have normal arteries at heart cath. One other patient with known coronary artery developed severe ischaemia during venipuncture, with ST elevation in the V-leads that resolved. Another patient, age 42 with emotional stress induced chest discomfort, developed very abnormal exercise test indicative of ischaemia, but later was shown to have normal coronary arteries. 1. Patients with normal coronary arteries, like patients with coronary artery disease, are at risk for acute coronary syndromes including sudden death, unstable angina, myocardial infarction, all during not so severe stress. 2. Health care workers should be aware of the potential for stress-induced symptoms, and stress-induced acute cardiac syndromes, even with simple procedures such as venipuncture. 3. Patients should be counselled that acute coronary syndrome, like chronic stress, can be cardiotoxic (AU)

Pulmonary edema associated with isoxsuprine therapy.

A 0.5% incidence of pulmonary edema was observed when the records of 1,407 patients treated with parenteral isoxsuprine over a 7-year interval were reviewed. Drug infusion rates were within the normal range in the seven affected patients. Discontinuation of therapy, oxygenation, and the administration of diuretics with or without digoxin were successful in reversing the process in all cases. Anemia, multiple gestation, and excessive intravenous fluids were identified as possible risk factors.

A placebo-controlled study to determine the efficacy of oral disopyramide phosphate for the prophylaxis of ventricular dysrhythmias after acute myocardial infarction.

1 To evaluate oral disopyramide phosphate in the prophylaxis of dysrhythmias occurring in acute myocardial infarction (MI) patients (presenting within 12 h of symptoms, age 21-70 years), a placebo-controlled, randomized double-blind, in hospital trial was conducted. After prognostic stratification (anterior and non-anterior MI at each of 4 regional hospitals) patients were randomly assigned to receive oral disopyramide phosphate (loading dose 150, 200, or 300 mg followed 6 h later by 100, 150, or 200 mg every 6 h for patients assessed to weigh less than 55, 55-85, or greater than 85 kg, respectively or matching placebo. The primary exclusion criteria were overt heart failure, systolic BP less than 100 mmHg, significant heart block or history of urinary retention. Active drug or placebo was continued for 7 days or until (a) detection of "warning arrhythmias' requiring i.v. lignocaine intervention (greater than 5 for 7 days or until (a) detection of "warning arrhythmias' requiring i.v. lignocaine intervention (greater than 5 premature ventricular contractions (PVCs)/min, R on T PVCs, multifocal PVCs, bigeminal PVCs, ventricular tachycardia or ventricular fibrillation) or (b) onset of exclusion criteria. In addition, plasma drug concentrations were determined and 24 h electrocardiographic tapes were obtained on day 1, and on one of days 4-7 but these results are not presented here. 2 Out of 121 patients entering the trial, 101 had confirmatory ECG and enzyme changes. Of these, 9 of 47 patients receiving disopyramide phosphate required lignocaine compared to 20 of 54 receiving placebo (19% v 37%; P = 0.047). Corresponding numbers for patients discontinuing trial medication for other non-fatal complications of MI were 5 and 3, and for those dying, were 3 (2 infarct extensions and 1 massive infarction), and 0, respectively. Respective numbers discontinuing trial medication for possible drug side effects (viz. urinary retention requiring catheterization) were 6 and 1 (P = 0.031). 3 In circumstances where i.v. therapy is deemed impractical, use of oral disopyramide phosphate given prophylactically in patients with acute MI may reduce the incidence of "warning arrhythmias' by a clinically significant extent.

Pulmonary veno-occlusive disease: antemortem diagnosis from roentgenographic and hemodynamic findings.

A 17-year-old boy with pulmonary veno-occlusive disease underwent Swan--Ganz catheterization. A normal pulmonary capillary wedge pressure was recorded in the presence of severe pulmonary arterial hypertension and roentgenographic evidence of pulmonary venous congestion. This triad of findings permitted an unequivocal diagnosis of pulmonary veno-occlusive disease, which was later confirmed at autopsy. The hemodynamics of this condition and of others included in the differential diagnosis are presented schematically.