Mitsunori Okamoto

Semiquantitative grading of severity of mitral regurgitation by real-time two-dimensional Doppler flow imaging technique

An attempt was made to determine whether mitral regurgitation could be detected and its severity evaluated semiquantitatively by newly developed real-time two-dimensional Doppler flow imaging in 109 patients who underwent left ventriculography. In the Doppler flow imaging technique, Doppler signals due to blood flow in the cardiac chambers are processed using a high speed autocorrelation technique, so that the direction, velocity and turbulence of the intracardiac blood flow are displayed in the color-coded mode on the monochrome B-mode echocardiogram in real time. Mitral regurgitant flow was imaged as a jet spurting out from the mitral valve orifice into the left atrial cavity. It was noted that the regurgitant jet in the left atrial cavity had a variety of orientations and dynamic features when studied by the present technique. The sensitivity of the technique in the detection of mitral regurgitation was 86% as compared with that of left ventriculography. Mitral regurgitation in the false negative cases was mostly mild. On the basis of the farthest distance reached by the regurgitant flow signal from the mitral valve orifice, the severity of regurgitation was graded on a four point scale and these results were compared with those of angiography. A significant correlation (r = 0.87) was found between Doppler imaging and angiography in the evaluation of the severity of mitral regurgitation. A similar result was obtained for the evaluation based on the area covered by the regurgitant signals in the left atrial cavity. Thus, noninvasive semiquantitative evaluation by real-time two-dimensional Doppler flow imaging appears to be a promising clinical technique.

Augmentation of atrial contribution to left ventricular inflow with aging as assessed by intracardiac Doppler flowmetry.

The influence of aging on the left ventricular (LV) function in diastole was investigated from the aspect of the mitral inflow pattern using 2-dimensional Doppler echocardiography. The subjects for the investigation were 69 persons who were diagnosed as healthy by a checkup examination. The peak velocity in the rapid filling phase and that in the atrial contraction phase tended to decrease and to increase with aging, respectively. However, these tendencies were not statistically significant. However, the ratio of the atrial contraction phase to the rapid filling phase showed a significant increase with aging (r = 0.82, p less than 0.001). Therefore, it is considered that the mitral flow conditions are influenced by aging. The result obtained is also interpreted to mean that the LV distensibility in early diastole is impaired with aging and that the contribution of the atrial contraction to LV filling is compensatorily augmented.

Evaluation of tricuspid regurgitation by pulsed Doppler and two-dimensional echocardiography.

We analyzed tricuspid regurgitation noninvasively using ultrasonic pulsed Doppler and twodimensional echocardiography in 66 patients in whom tricuspid regurgitation was suspected from routine clinical evaluation. All of the patients also underwent right ventriculography. Ten healthy subjects served as controls. In 62 of 66 patients, the study was adequately performed. In 58 of 62 patients, pansystolic abnormal Doppler signals were detected in the right atrial cavity, and were interpreted to indicate tricuspid regurgitant flow. Two-dimensional echocardiograms in the parasternal four-chamber view demonstrated that the region in which the abnormal Doppler signals were detected was spindle-shaped and extended from the tricuspid orifice toward the right atrial posterior wall parallel to the interatrial septum. The severity of regurgitation was graded on a four-point scale, based on the distance reached by the abnormal signals from the tricuspid orifice toward the posterior wall. For comparison, the right ventriculograms were evaluated on a four-point scale similar to the Sellers classification of mitral regurgitation. The grades by the two methods matched exactly in 36 cases, differed by one level in 23 and by two levels in three. Thus, the two methods showed a good correspondence. Similar results were obtained for the grading based on the area covered by the abnormal signals. We conclude that noninvasive grading of tricuspid regurgitation by ultrasonic pulsed Doppler and two-dimensional echocardiography is practicable.

Clinical applications of a new type of real-time two-dimensional Doppler flow imaging system

The clinical significance of a newly developed real-time 2-dimensional (2-D) Doppler flow imaging technique was assessed. In the instrumentation of the echocardiograph, the pulsed Doppler mechanism was incorporated in a wide-angle, phased-array system. The Doppler flow signals obtained from the cardiac chamber were processed on the basis of the autocorrelation principle. The direction, velocity and variance of the intracardiac blood flow were calculated in real time and displayed in the color-coded mode on the television screen, and were superimposed on the 2-D echocardiographic image of the heart. The technique was used in 20 healthy subjects and 100 cardiac patients. The new technique clearly visualized the whole aspect of intracardiac blood flow by the cine mode in real time; thus, the technique may be called Doppler cineangiocardiography. The mitral inflow and the aortic ejection flow were clearly demonstrated. A regurgitant jet from the valve orifices was dynamically visualized as seen in the cineangiogram. The spatial orientation and extent of the regurgitant jet were easily assessed. The jet stream through the stenotic mitral orifice was well imaged in the left ventricular cavity, showing a variety of stream directions. Intracardiac shunts in ventricular septal defect and atrial septal defect were clearly visualized. The defect could be localized on the interventricular septum on the basis of the site where the shunt flow spurted, although the echocardiographic interruption was not demonstrated in the 2-D echocardiographic image of the cardiac structure. Although some technical problems remain, our new technique greatly improves the diagnostic efficacy of ultrasound.

Abnormal systolic blood pressure response during exercise recovery in patients with angina pectoris

OBJECTIVES This study was conducted to clarify the mechanisms of the abnormal systolic blood pressure response after exercise in patients with angina pectoris. BACKGROUND An abnormal systolic blood pressure response in patients with angina pectoris has been observed not only during exercise but also during the recovery period after exercise. However, the mechanisms of this abnormal response during recovery have not been elucidated. METHODS Thirty-five patients with angina pectoris and 17 control subjects underwent bicycle ergometric studies after insertion of a Swan-Ganz catheter. RESULTS In control subjects, all hemodynamic variables decreased rapidly after exercise. In 7 of the 35 patients, systolic blood pressure increased after exercise. The patients with angina were classified into two groups. In group I (17 patients), changes in systolic blood pressure during recovery were smaller than those in control subjects. In group II (18 patients) recovery of systolic blood pressure was normal. Changes in stroke index from rest to peak exercise were smaller in group I than in group II. Stroke index in both patient groups increased paradoxically during recovery. The increase in systemic vascular resistance index during recovery and the ratio of plasma norepinephrine concentration to cumulative work load were greater in group I than in group II. CONCLUSIONS An abnormal systolic blood pressure response after physical exercise in patients with angina pectoris is indicative of severe myocardial ischemia during exercise and may be caused by an increase in stroke volume due to recovery from myocardial ischemia and increased systemic vascular resistance secondary to exaggerated sympathetic nervous activity.

Doppler echocardiographic features of ventricular septal rupture in myocardial infarction

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.

Relation between collateral flow assessed by Doppler guide wire and angiographic collateral grades

We investigated the relation between the angiographic collateral grade (Rentrops classification) and the collateral flow velocity pattern in 43 patients with angina pectoris. Collateral flow velocity was measured with a Doppler guide wire during balloon occlusion in coronary angioplasty. Collateral flow was detected in 21 of the 43 patients. In 6 of the 21 patients, collateral vessels were not seen angiographically before angioplasty. The direction of collateral flow was classified as forward, backward, or bidirectional. Forward and backward collateral flows were seen in all angiographic grades. Bidirectional collateral flows were observed only in grades 0 to 2. The peak collateral flow velocity was not correlated with the angiographic grades, but the ratio of the collateral flow duration to a cardiac cycle length was correlated with them (grade 0, 44% +/- 15%; grade 1, 70% +/- 16%; grade 2, 84% +/- 11%; and grade 3, 93% +/- 3%; p < 0.0005, analysis of variance). The peak velocity integral was also correlated with the angiographic collateral grades (p < 0.05; analysis of variance). The peak velocity integral was also correlated with the angiographic collateral grades (p < 0.05; analysis of variance). Electrocardiographic signs of ischemia were less observed in patients with unidirection and longer duration of collateral flow pattern (p < 0.05, respectively). A Doppler guide wire may be useful in assessing collateral flow grade.

Intralymphocytic sodium and free calcium and plasma renin in essential hypertension.

Intraceilular sodium, potassium, and free calcium concentrations were investigated in lymphocytes of 30 patients with essential hypertension and 30 normotensive controls. All subjects were placed on a diet containing 8 to 10 g of sodium chloride per day. Lymphocyte sodium concentration was higher in hypertensive patients than in normotensive controls (19.8 ± 1.8 vs 18.4 ± 1.8 mmol/kg wet weight; p < 0.01), whereas lymphocyte potassium concentration was similar in both groups. Lymphocyte free calcium concentration was also higher in hypertensive patients than in normotensive controls (134.6 ± 13.2 vs 120.2 ± 16.4 nmol/L; p < 0.01). There was a positive correlation between lymphocyte sodium and free calcium concentrations in normotensive controls, in hypertensive patients, and in the subjects combined (r = 0.59, p < 0.01; r = 0.71, p < 0.001; and r = 0.70, p < 0.001, respectively). Lymphocyte potassium concentration was not related to lymphocyte sodium or free calcium concentration in each group. In patients with essential hypertension, intraceilular sodium and free calcium concentrations were negatively correlated with plasma renin activity (r = −0.66, p < 0.001; r = −0.60, p < 0.001, respectively), but they were not related to age, mean blood pressure, serum electrolyte concentration, or plasma norepinephrine concentration. These results suggest that a considerable relationship exists between intraceilular sodium and free calcium in lymphocytes and that, in essential hypertension, the alteration in cellular metabolism of sodium and calcium may be linked to the renin system but not to blood pressure, age, or adrenergic activity.

Pulmonary regurgitation studied with the ultrasonic pulsed Doppler technique.

Sixty patients with pulmonary regurgitation were studied by the pulsed Doppler technique combined with two-dimensional and M-mode echocardiography. Patients with pulmonary regurgitation had abnormal Doppler signals just below the pulmonic valve in the right ventricular outflow tract in diastole on the two-dimensional image. These signals were considered to indicate the regurgitant flow. There are two patterns of pulmonary regurgitant Doppler signals. In pulmonary hypertension, the maximal component of instantaneous flow velocity is sustained at about the same signal strength throughout diastole, but when the pulmonary arterial pressure is normal, the velocity slows down gradually from early diastole to end-diastole. Pulmonary regurgitation was detected by phonocardiography in about half the patients. In the remaining half, pulmonary regurgitant murmur could not be differentiated from aortic regurgitant murmur or was masked by coexistent aortic regurgitation or patent ductus arteriosus, whereas the Doppler technique indicated pulmonary regurgitation.

Periarteritis of coronary arteries with severe eosinophilic infiltration. A new pathologic entity (eosinophilic periarteritis)

A 40 year-old male presented symptoms of angina pectoris for about nine years and expired with symptoms of unstable angina, changing pattern at the terminal stage. At autopsy, both right and left coronary arteries of the subepicardial region were grayish white and elastic hard. Histologically, inflammatory infiltration was localized in adventitia of coronary arteries located in the subepicardial region. Inflammatory cells infiltrated into the adventitia were mostly eosinophiles. The medial smooth muscle cells were well preserved and the intima showed irregular thickening with fibrosis. Vascular obstruction or recanalization could not be observed. As a result of these findings, it was considered that these inflammatory changes of the coronary arteries could be termed eosinophilic periarteritis. These inflammatory changes could not be found in the intramural coronary arteries. Rather extensive fibrosis could be seen in the muscle layer centering about the posterior wall of the left ventricle. No findings of angiitis could be detected in the blood vessels except subepicardial coronary arteries.