Clinical cardiology
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Clinical cardiology · Jun 1984
Left ventricular function during atrial pacing: a radionuclide angiographic study.
Multigated radionuclide angiography was performed at rest and during atrial pacing in 10 normal subjects. Left ventricular volumes in diastole and systole were measured by total counts in the region of interest of the left ventricle. ⋯ Ejection fraction rate increased and the uncorrected ejection rate decreased with the increase in heart rate. The normal response to tachycardia induced by atrial pacing was a decrease in ventricular volumes without a change in ejection fraction or cardiac output.
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Clinical cardiology · Mar 1984
Case ReportsAdverse reactions to protamine sulfate following cardiac surgery.
We report four patients who developed severe adverse reactions to protamine sulfate following cardiac surgery. Two types of reactions were seen. First, an immediate anaphylaxis which is a complement-dependent IgG antibody-mediated reaction. ⋯ The second reaction to protamine during cardiac surgery is characterized by delayed onset and profound vascular damage presenting as noncardiogenic pulmonary edema or total vascular collapse with prolonged hypotension and anasarca. These patients have negative skin tests and in our studies, no evidence of antibody mediated reaction, suggesting some other mechanisms may play a part. The mortality is high (30% of patients reported) and survivors have significant morbidity.
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Clinical cardiology · Aug 1983
Can the mode of death be predicted in patients with angiographically documented coronary artery disease?
To determine whether sudden versus non-sudden cardiac death could be predicted in high risk patients, 1157 medical patients were followed for an average of 46 months after a diagnostic coronary angiogram and 18 clinical, hemodynamic, and angiographic variables known to be associated with a high risk of mortality were analyzed. The total group of 141 deaths was classified into 3 subgroups: (1) 82 sudden deaths (less than 1 hour after onset of symptoms); (2) 46 deaths due to acute myocardial infarction with or without heart failure, and (3) 13 deaths unrelated to cardiac symptoms. In a subset of 64 patients, the duration of electrical systole (QTc) was calculated before angiography and before death. ⋯ Patients dying suddenly did not present new infarctions during follow-up whereas patients dying from acute myocardial infarction had a 13% incidence of prior infarction and a higher incidence of heart failure. In addition, QTc at entry was longer in nonsurvivors than in normal subjects (p less than 0.0001) and patients experiencing sudden death exhibited the highest incidence of QTc prolongation (greater than or equal to 440 ms) during follow-up (p less than 0.05). We conclude that: (1) although the severity of coronary disease and left ventricular dysfunction are closely related to cardiac mortality, they do not discriminate between sudden and nonsudden cardiac deaths; (2) patients experiencing sudden death are characterized by a low incidence of new myocardial infarction or congestive heart failure and prolongation of the QTc interval during follow-up.
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Clinical cardiology · Mar 1983
Fully automated ambulatory blood pressure in the diagnosis and therapy of hypertension.
Technical characteristics of a fully automatic apparatus for ambulatory semicontinuous blood pressure monitoring are described. Initially, we ascertained the reliability and the fidelity in the reproduction of studied events (blood pressure, heart rate, ECG). Good results were obtained, even in comparison with other methods (blood pressure semiautomatic or invasive monitoring). ⋯ The easy applicability of this method allowed us to demonstrate blood pressure variability over a 24-h patient period. We now can evaluate the factors contributing to blood pressure variability and the alterations contributing to the meaning of circadian rhythm. We are now able to comment on the prevalent incidence of organic or neurogenic components in single hypertensive states, the possible coexistence of asymptomatic coronary heart disease, and on the choice and efficacy of hypotensive drugs.
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Clinical cardiology · Aug 1982
Case ReportsProlonged persistence of a large pericardial effusion and hemodynamic evidence of cardiac tamponade during treatment of myxedema.
We describe clinical, echocardiographic, and catheterization findings that were present initially and during therapy in a myxedematous patient with a large pericardial effusion and tamponade. Treatment with thyroxine resulted in a marked improvement of most of the clinical features of hypothyroidism and some improvement in cardiac function. ⋯ These findings are consistent with evidence of an abnormality of pericardial drainage that persists for months after other thyroid hormone dependent functions are normalized by thyroxine replacement. Therefore prompt surgical drainage rather than dependence on medical therapy alone is indicated in myxedematous patients who have cardiac tamponade.