Assessment of left atrial function in patients with hypertensive heart disease.

Abstract

SUMMARY Left atrial function in patients with hypertensive heart disease was compared with that in control subjects. In patients with hypertensive heart disease, the time constant of left ventricular relaxation was significantly greater than that in controls (54 ± 18 vs 31 ± 16 msec; p<0.01). The ratio of left ventricular filling volume before atrial contraction (left atrial reservoir volume/left atrial emptying volume before atrial contraction, and conduit volume/flow volume from the pulmonary vein into the left ventricle) to left ventricular stroke volume was significantly smaller than that in controls (65 ± 13 vs 76 ± 7%; p<0.05). In patients with hypertensive heart disease, the ratio of reservoir volume to stroke volume was not significantly different from that in controls, while the ratio of conduit volume to stroke volume was significantly smaller than that in controls (43 ± 13 vs57 ± 9%;p<0.05). The latter ratio was inversely correlated with the time constant of left ventricular relaxation (r = -0.05, p<0.05). In patients with hypertensive heart disease, the ratio of left ventricular filling volume during atrial contraction to stroke volume was significantly larger than that in controls (35 ± 13 vs 24 ± 7%; p<0.05). The ratio of left ventricular filling volume during atrial contraction to stroke volume had a significant inverse correlation with the ratio of conduit volume to stroke volume (r = -0.84, p<0.001). In patients with hypertensive heart disease, left atrial work was significantly greater than that in controls (274 ± 101 vs 94 ±42 mm Hg ml; p<0.001). Thus, patients with hypertensive heart disease had impaired left ventricular diastolic filling before atrial contraction, which resulted in the decreased left atrial conduit volume. However, the left ventricular stroke volume was maintained by the increased left atrial emptying volume during atrial contraction. cardiac performance in the diseased heart has been considered previously.'" 10 The left atrium may serve as a conduit for the passage of blood from the pulmonary veins to the left ventricle during early left ventricular filling, as a reservoir for storing blood during left ventricular systole, and as a contractile chamber for augmentation of left ventricular filling. Understanding each of these functions and the contribution of the left atrium to left ventricular function in normal and diseased hearts is important. Electrocardiographic left atrial abnormalities" and the appearance of atrial gallop rhythm on cardiac ausculta- Received August 28, 1985; accepted February 12, 1986. tion 12 have been documented in patients with hypertensive heart disease. Recently, echocardiography has been used to observe left atrial function in hypertensive patients. 13 In these previous studies, the left atrial abnormalities were discussed in association with the abnormal diastolic function of the left ventricle, but further delineation of the significance and pathophysiology of the findings was not pursued.In the present study, the changes in reservoir, condu...

<b>Value of Left Atrial Function in Predicting Exercise Capacity in Heart Failure With Moderate to Severe Left Ventricular Systolic Dysfunction</b>

“…[26][27][28] In patients with LV dysfunction, the LA contribution to LV filling becomes more important. 29,30) In the early stages of LV systolic dysfunction, early ventricular diastolic inflow is decreased, and consequently atrial passive emptying is decreased and atrial active pumping function in late diastole is increased. 8) In this way, the LA reservoir, conduit, and pumping functions are reorganized and thus cardiac output is maintained.…”

Change of left atrial systolic pressure waveform in relation to left ventricular end-diastolic pressure.

“…The Left atrial contraction provides a significant increment of blood to the left ventricle, stretching the ventricle and priming it for ventricular ejection. [2][3][4][5][7][8][9][10][11][12][13][14][15][16] The a wave of the left atrial pressure waveform or left atrial systolic pressure pulse is believed to result from left atrial contraction. The present study demonstrates a previously unrecognized biphasic left atrial systolic pressure waveform and describes the relation of the change in this pressure pattern to left ventricular end-diastolic pressure.…”

Compensatory increase of left atrial external work to left ventricular dysfunction caused by afterload increase

“…Hence, atrial active contraction and relaxation play important roles in these patients. Matsuda et al (14) reported that patients with hypertensive heart disease had impaired LV diastolic filling in parallel with the decreased LA conduit function, but LV stroke volume was maintained by the increased LA emptying volume during atrial contraction. In that study, LA pressure was measured by a Millar catheter-tip micromanometer and volume was measured by cineangiograph, and LA pressure-volume loops were constructed that were similar to the ones in our acute experiments.…”