Systolic time intervals in chronic obstructive pulmonary disease

Systolic time intervals and their derivatives for evaluation of cardiac function

Systolic time intervals provide a noninvasive indication of global left ventricular performance, are relatively sensitive, and are easily obtained from an M-mode echocardiogram. This paper defines systolic time intervals (preejection period, left ventricular ejection time, and total electromechanical systole) and their derivatives (preejection period/left ventricular ejection time and velocity of circumferential fiber shortening). Their utility and weaknesses, as well as the effects of heart rate, loading conditions, cardiac contractility, and drug therapies on systolic time intervals are discussed. Normal values for systolic time intervals for the dog and cat are provided.

Pathologic involvement of the left ventricle in chronic cor pulmonale

To determine whether or not the left ventricle is pathologically involved in patients with chronic cor pulmonale, right and left ventricular weights, wall thickness, myocyte diameters, and percentage of fibrosis in 18 autopsied hearts were examined in patients with chronic pulmonary disease (CPD); ten had right ventricular hypertrophy on their electrocardiograms, and eight were without right ventricular hypertrophy. Five with extracardiopulmonary disease were used as controls. The weight of the right ventricle was significantly increased in CPD when compared to control subjects. Walls of both ventricles were significantly thicker in CPD. Myocyte diameters of both ventricles were significantly greater in CPD. The percentage of fibrosis in the right ventricle was significantly greater in CPD. The percentage of fibrosis in the left ventricle was significantly greater only in patients with right ventricular hypertrophy. We concluded that the left ventricle was also involved pathologically in patients with chronic cor pulmonale in the end stage of the disease.

Interdependence of the left and right ventricles in health and disease

Since the publication of Bernheim's report it has been clear that the anatomic and functional integrity of each ventricle is an important determinant of the functional characteristics of the other ventricle. How the ventricles interact in health and disease has been of interest to many investigators. This article reviews and considers the structure and function of each ventricle as an independent subunit and as a unified pumping system in the healthy state and in various disease states.

Right and left ventricular dysfunction in patients with chronic obstructive lung disease. Assessment by first-pass radionuclide angiography

To evaluate the relationship between right and left ventricular function in patients with obstructive lund disease, we studied 10 normal subjects (group 1) and 37 patients with chronic obstructive pulmonary disease by first pass radionuclide angiography. These 37 patients were divided into three groups: nine with mild chronic obstructive pulmonary disease (group 2), 20 with severe chronic obstructive pulmonary disease (group 3) and eight with severe chronic obstructive pulmonary disease and primary left ventricular disease (group 4). In each subject right ventricular ejection fraction (RVEF), left ventricular ejection fraction (LVEF) and ejection fraction during first third of systole (first third LVEF) were calculated. (For table: see text.) p less than 0.05 versus 1. All subjects in group 2 had normal left ventricular and right ventricular function. In group 3, 11 of 10 (55 per cent) had a low RVEF and three of 20 (15 per cent) a low LVEF. However eight of 20 in this group (40 per cent) had a depressed first-third LVEF. The correlation between decline in RVEF and first-third LVEF was good r = 0.73. We conclude that (1) certain indices of early systolic left ventricular ejection are abnormal in many patients with chronic obstructive pulmonary disease and correlate with the decline in right ventricular function; (2) this is not seen in patients with mild chronic obstructive pulmonary disease and is worse in patients with underlying left-sided heart disease.

Noninvasive evaluation of ventricular function in cystic fibrosis

The cardiac function of 21 patients with cystic fibrosis was studied using radionuclides and M-mode echocardiography. The patients (mean age 13.2 years, range 4 to 27) had a wide range of clinical and pulmonary function abnormalities (mean Shwachman-Kulczycki score 62.1). Decreased right ventricular ejection fraction was found in 13 of 18 patients (72%); an additional four patients had abnormal septal motion on ECHO. Left ventricular ejection fraction was abnormal at rest in four patients (19%); an additional four patients had borderline low LVEF. The LV pre-ejection period to ejection time ratio increased significantly (i.e., worsening LV performance) with deterioration of S-K score, chest radiograph score, and forced expiratory volume in 1 second. Three of eight patients with normal LVEF at rest had an abnormal response to supine bicycle exercise: LVEF fell in two patients and was unchanged in one. Thus evidence of LV dysfunction was observed in seven of 21 (33%) of the patients; four at rest and in three only during exercise.

Left ventricular function in chronic obstructive pulmonary disease

The presence or absence of left ventricular dysfunction in chronic obstructive pulmonary disease has been debated for decades. I have reviewed the following evidence pertaining to this topic: (1) left ventricular pathologic abnormalities; (2) the methods used to determine left ventricular performance; (3) specific abnormalities of left ventricular function as revealed by systolic time intervals, left ventricular end-diastolic pressure, ejection fraction, isovolumic indices, and left ventricular function curves; and (4) pertinent experimental data. The bulk of the evidence indicates that the clinical symtoms of left-sided failure are unreliable in those with obstructive disease of the airways and that the great majority of patients have normal left ventricular function, once other causes are excluded. A small group of patients have some abnormalities in left ventricular performance, but these have not been clinically significant. The ultimate importance of such abnormalities awaits future investigation.