Harold T. Dodge

Quantitative Angiocardiography I. The Normal Left Ventricle in Man

Quantitative angiocardiography has been utilized to study the left ventricle of seven women and 15 men who had no evidence of heart disease. The left ventricular enddiastolic volume, end-systolic volume, and stroke volume were calculated in 15 individuals and left ventricular mass was determined in all 22 subjects. The mean end-diastolic volume was 70 cc/m.2 The left ventricular wall thickness during diastole averaged 8.9 mm for women and 11.9 mm for men and the mean left ventricular mass was 76 g/m2 for women and 99 g/m2 for men. The ventricular volumes did not correlate well with age, sex, body surface area, or weight, but correlated in a negative manner with heart rate. There was a significant difference between left ventricular wall thickness and mass in normal men and women. Values for normal left ventricular volumes obtained by other investigators using angiocardiographic and indicator-dilution methods are compared with the results of this study. The values obtained for left ventricular mass by the angiocardiographic method used in this study are similar to those obtained by other investigators in postmortem hearts.

Mitral Regurgitation in Early Myocardial Infarction: Incidence, Clinical Detection, and Prognostic Implications

OBJECTIVEnTo investigate mitral regurgitation occurring early in the course of acute myocardial infarction with respect to its incidence, the impact of infarct size and location, the accuracy of clinical detection, the contribution of global and regional left ventricular performance, and its influence on prognosis.nnnDESIGNnProspective observational study derived from patients entering Phase I of the Thrombolysis in Myocardial Infarction (TIMI) trial.nnnSETTINGnMulticenter trial involving 13 university-affiliated medical centers.nnnPATIENTSnA total of 206 patients studied within 7 hours of symptom onset during their first myocardial infarction.nnnMEASUREMENTSnContrast left ventriculography was used to document mitral regurgitation.nnnRESULTSnMitral regurgitation was present in 27 patients (13%). Although the presence of regurgitation correlated with the site of infarction (20 of 27 had anterior infarctions) and the number of akinetic chords, it was not statistically related to the peak creatine kinase value or to left ventricular chamber size or filling pressure. A murmur of mitral regurgitation was heard in only 2 patients (1 incorrectly). The presence of early mitral regurgitation predicted cardiovascular mortality at 1 year by univariate (relative risk, 12.2; 95% Cl, 3.5 to 42; P less than 0.0001) and multivariate (relative risk, 7.5; Cl, 2.0 to 28.6; P = 0.0008) analyses.nnnCONCLUSIONSnMitral regurgitation in early myocardial infarction is generally clinically silent, is more common in anterior infarction, is associated with regional dysfunction but not early ventricular dilation or peak enzyme release, and is an important predictor of cardiovascular mortality.

Hemodynamic aspects of heart failure

Abstract Heart failure may occur as a result of failure of the contractile mechanisms of the myocardium, a large pressure-volume load imposed on the heart, or a combination of an increased load and diminished contractility. In patients with chronic heart disease, the consequences of an increased volume load are cardiac dilatation and hypertrophy appropriate for the volume load. Chronic pressure loads are associated with ventricular hypertrophy but essentially normal left ventricular end-diastolic volume and systolic ejection fraction. Myocardial disease in itself, or in association with conditions that place an added mechanical burden on the left ventricle, is characterized by inappropriate dilatation and hypertrophy of the left ventricle. Failure of these mechanisms of dilatation and hypertrophy to compensate for myocardial disease or work load results in the hemodynamic alterations associated with heart failure.

Left Ventricular Anatomical and Functional Abnormalities in Chronic Postinfarction Heart Failure

Abstract Fifty patients with chronic postmyocardial infarction heart failure had quantitative biplane angiocardiography; 42 also had coronary angiography. Mitral regurgitation, localized ventricula...

Ventricular Dynamics in Atrial Fibrillation

During atrial fibrillation there are beat-to-beat changes of ventricular rate, end-diastolic volume, end-diastolic pressure, and arterial pressure or resistance to ventricular ejection. The effect of these variables on left ventricular dynamics in man has been approached by studying single sequences of beats in patients with atrial fibrillation. An index of changes of left ventricular volume has been determined from the electrokymogram of left cardiac border. Left ventricular pressures have been measured at surgery or by the transbronchial technic. These studies provide a better understanding of the hemodynamics of the left ventricle during atrial fibrillation and demonstrate another approach to the study of left ventricular function in man.

Functional Characteristics of the Left Ventricle in Heart Disease

Abstract Angiocardiographic methods for determining left ventricular volume, volume changes, and mass have been applied to further define the functional characteristics of the left ventricle in hea...

Quantitative and qualitative coronary arteriography

The clinical objectives of arteriography are to obtain information that contributes to an understanding of the mechanisms of the clinical syndrome, provides prognostic information, facilitates therapeutic decisions, and guides invasive therapy. Quantitative and improved qualitative assessments of arterial disease provide us with a common descriptive language which has the potential to accomplish these objectives more effectively and thus to improve clinical outcome. In certain situations, this potential has been demonstrated. Clinical investigation using quantitative techniques has definitely contributed to our understanding of disease mechanisms and of atherosclerosis progression/regression. Routine quantitation of clinical images should permit more accurate and repeatable estimates of disease severity and promises to provide useful estimates of coronary flow reserve. But routine clinical QCA awaits more cost- and time-efficient methods and clear proof of a clinical advantage.

Unstable Angina: Guidelines for Therapy Based on the Last Decade of Clinical Observations

Excerpt The prognosis and best therapy for unstable angina, a diagnostic label that has been applied to a spectrum of clinical presentations in patients with (and without) coronary disease, have be...

Effects of increasing left ventricular filling pressure in patients with acute myocardial infarction

Left ventricular performance in 19 patients with acute myocardial infarction has been evaluated by measuring left ventricular response in terms of cardiac output, stroke volume, work, and power to progressive elevation of filling pressure accomplished by progressive expansion of blood volume with rapid infusion of low molecular weight dextran. Such infusion can elevate the cardiac output, stroke volume, work, and power and thus delineate the function of the left ventricle by Frank-Starling function curves. Left ventricular filling pressure in the range of 20-24 mm Hg was associated with the peak of the curves and when the filling pressure exceeded this range, the curves became flattened or decreased. An increase in cardiac output could be maintained for 4 or more hr. Patients with a flattened function curve had a high mortality in the ensuing 8 wk. The function curve showed improvement in myocardial function during the early convalescence. When left ventricular filling pressure is monitored directly or as pulmonary artery end-diastolic pressure, low molecular weight dextran provides a method for assessment of left ventricular function.

Quantitative Arteriography in Coronary Intervention Trials: Rationale, Study Design, and Lipid Response in the University of Washington Familial Atherosclerosis Treatment Study (FATS)

The current technology with greatest precision and statistical efficiency for studying the natural course and the therapy of coronary atherosclerosis is the quantitative analysis of lesion change from serial arteriograms. This approach was used in 47 patients who were electively recatheterized 18 months after the clinically indicated arteriograms, in whom 642 disease coronary segments were identified, representing the entire spectrum of minimal-to-severe atherosclerosis. The frequency distribution of change in the “percent stenosis” (%S) parameter was a bell-shaped curve centered at + 1.6% (average increase in percent stenosis in all lesions in 18 months), with a standard deviation of + 8%. Using three standard deviations of the short-term variability of the Poiseuille flow resistance estimate as a criterion for “true” lesion change, we found that 13.4% of all lesions progressed in 18 months. On average, 16% of all lesions progressed in patients with hyperlipidemia, as compared with 9.9% of lesions in normo-lipidemic patients (p = 0.036).