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Contrast angiography provides much information about ventricular and valvular size and function. This review describes the calculation of left ventricular chamber volume and wall thickness and the derivation of ejection fraction, cardiac output, mass and wall tension and stress. In patients with valvular regurgitation, valve orifice area can be calculated by using the angiographic output and regurgitant flow determined by comparing the angiographic output with the cardiac output measured using Fick or indicator-dilution techniques. By analyzing ventricular volume in conjunction with pressure, it is possible to assess pressure-volume work, compliance and contractility. Regional wall motion can be measured from the change in ventricular contour with time. When applied clinically, these methods and measurements have been used to determine the hemodynamic characteristics of the compensated and decompensated left ventricle in valvular and coronary heart disease. The information derived from quantifying information in angiographic images contributes to patient diagnosis, assessment of prognosis and evaluation of therapy, and has added to our knowledge concerning the pathophysiology of heart disease.

Pulsed Doppler echocardiography (PDE) is a technique for evaluating blood flow characteristics at specific locations within the heart and great vessels. Because this method assesses blood flow rather than cardiac structures, PDE complements the findings of M-mode echocardiography. A new on-line graphical method for displaying pulsed Doppler information provides 1) a printed, permanent record of flow information, 2) precise timing of blood flow events, and 3) information on the direction of flow in the heart and great vessels.

In this study the effects of coronary artery bypass surgery on ventricular function were evaluated at rest by quantitative analysis of segmental wall motion on cineventriculography, and during maximal treadmill exercise by measurement of serial cardiac outputs (Fick method) with the use of indwelling pulmonary artery and radial artery catheters. The patient had single vessel coronary disease and exertional angina. Following placement of a bypass graft to the proximally occluded left anterior descenting coronary artery, and despite the presence of arterial hypoxemia secondary to interstitial pulmonary fibrosis, a striking increase in maximal cardiac output occurred, mediated by a rise in both maximal heart rate and stroke volume. In this patient, resting ventricular volumes and ejection fraction were normal both before and after surgery, but preoperative abnormalities in extent of segmental wall motion, identified quantitatively, were restored to normal after bypass grafting. These investigations indicate that bypass surgery can provide substantial physiologic benefits in addition to providing subjective relief of anginal symptoms.

The immediate effect of contrast medium injection on left ventricular (LV) volume, stroke volume (SV) and ejection fraction (EF) was evaluated from postoperative LV biplane cineangiograms of 10 patients with 4-6 epicardial markers placed at the time of coronary artery surgery. After calibrating marker distances with respect to volume (r = 0.97-0.99) over one cardiac cycle for each patient, regression equations were used to compute LV volume from marker measurements for beats prior to, during and following injection. End-diastolic volumes (EDV) prior to injection ranged from 93-263 ml and did not change significantly with injection. End-systolic volumes (ESV) showed a mean decrease of 7.3 ml by beat 7 following injection; this was of borderline significance. Similarly, there was no significant change of SV or EF until beat 7 when there were small but significant increases of 6.4 ml and 0.04, respectively. The injection of moderate amounts of contrast in man does not cause significant changes in LV volume or EF through the sixth post-injection beat.

We assessed the prognostic value of cardiothoracic ratio and plain film heart volume in relation to other clinical, exercise, hemodynamic and quantitative angiographic variables. Both cardiothoracic ratio and plain film heart volume are highly sensitive, but nonspecific, indicators of abnormal left ventricular end-diastolic volume and ejection fraction. Both variables are univariately important predictors of survival in cohorts of medically and surgically treated heart disease patients. Plain film heart volume significantly adds to the multivariate prediction of prognosis obtained from groups of clinical, exercise, hemodynamic and quantitative angiographic variables. These measurements from the routine chest roentgenogram are sensitive detectors of abnormal left ventricular function or volume and important predictors of long-term survival. The fact that they contribute prognostic information in addition to left ventricular volume and ejection fraction suggests that other cardiac chamber volumes are of prognostic importance.

Thrombolytic therapy for acute myocardial infarction reduces early mortality, but full recovery of left ventricular function after reperfusion is delayed. Therefore, the relations among reperfusion, survival and the time course of left ventricular functional recovery were examined in 226 patients treated with intracoronary streptokinase; 77% (134 patients) had sustained reperfusion and 31 patients had no reperfusion or had reocclusion by day 3. Wall motion was measured from contrast ventriculograms performed in the acute period and 3 days later in the central and peripheral infarct regions and the noninfarct region by the centerline method in 165 patients. Patients with reperfusion had better survival (p less than 0.05, mean follow-up 4.5 years) and a higher ejection fraction at 3 days (52 +/- 12 versus 46 +/- 10%, p less than 0.02) attributable to a significantly different change in peripheral infarct region function between the acute and 3 day studies (0.1 +/- 1.0 versus -0.3 +/- 0.9 SD, p less than 0.05). These early functional changes were significant in patients with anterior myocardial infarction and showed similar trends in those with inferior myocardial infarction. On Cox regression analysis, function measured at 3 days was more predictive of survival than was function measured acutely (chi square for acute ejection fraction = 11.48 versus 24.59 at 3 days). Although, as previously reported, greater than 45% of total recovery of left ventricular function occurs later, the ejection fraction achieved by day 3 is already predictive of survival. Thus, the mechanism by which successful thrombolytic therapy enhances survival is improvement of regional and global left ventricular function early after acute myocardial infarction.