Echocardiographic evaluation of right heart responses to sublingual nifedipine in dilated cardiomyopathy.

Twelve patients with dilated cardiomyopathy were studied in order to evaluate whether the favourable effect of Nifedipine on the right heart is due to a direct action of the drug on pulmonary resistances or is related to an improvement of left ventricular function. Echocardiographic examination of left and right heart was performed at basic conditions, after Nifedipine treatment--20 mg sublingually--and after 20 minutes of oxygen breathing (FiO2 75%). This was done in order to verify if oxygen vasodilating action could potentiate the Nifedipine effect.

Echocardiographic evaluation of inferior vena cava wall motion and pulmonary flow velocity responses to sublingual nifedipine.

Echocardiographic and cardiac catheterization were used to test the effect of Nifedipine, sublingually administered, on the right heart function and pulmonary flow velocity and pressure in 25 cases. Systolic and mean pulmonary pressure, wedge pressure, mean right atrial and ventricular end-diastolic pressure, aortic pressure, and total pulmonary resistance decreased after Nifedipine in 10 patients who underwent diagnostic cardiac catheterization. While pulmonary flow velocity, expressed as the slope of the contrast echo lines on the pulmonary valve, increased as a mean value after Nifedipine, it showed different behaviour in single cases and thus failed to provide any reliable conclusion as to the effect of Nifedipine.

Contrast echocardiographic features of pulmonary hypertension and regurgitation.

Linear contrast echo configuration on the pulmonary valve M-mode echogram was assessed in 28 patients with pulmonary hypertension, in 10 with pulmonary regurgitation, and in 10 normal subjects. Contrast echo parallel lines filling the total systolic phase of the pulmonary valve were recorded in normal subjects. Contrast echo lines stopping in early systole around the pulmonary valve mid-systolic notch were seen in all the patients with pulmonary hypertension in relation to changes with the pulmonary flow.

Subxiphoid echocardiographic assessment of left ventricular wall in old myocardial infarction.

We studied by cineangiography and standard and subxiphoid echocardiography the left ventricular wall motion in 50 patients with old myocardial infarction and 10 normal subjects. Coronary artery angiography showed a good correlation with the electrocardiographic site of infarction and with the asynergic areas detected by cineventriculographic examination and bidimensional echocardiography. From the correlation of data related to the asynergic areas detected by angiographic and echocardiographic methods it was possible to establish that subxiphoid approach allows to visualize the posterior-lateral wall whereas the parasternal approach the posterior-inferior wall of the left ventricle.

[Electrophysiological evaluation of ventricular tachycardia by right and left ventricle endocardial mapping (author's transl)].

Eight patients with ventricular tachycardia (VT) have been studied by unipolar recordings of 7 endocardial points of the left ventricle (LV) and 6 endocardial points of the right ventricle (RV) in order to record if possible: 1) where the VT arose; 2) a continuous electrical activity during the sistodiastolic phase of the intracardiac ECG [late potentials (LP)], suggesting the reciprocating mechanism of VT. All the patients underwent cardiac catheterization with left and/or right ventriculography. A coronary arteriography was performed in four cases.

[The endocardial ventricular activation map in a case of intermittent BBS in phase III (author's transl)].

To obtain information on endocardial activation-sequence, unipolar recordings at seven left ventricular and six right ventricular points were performed in a 37-year-old man suffering from cardiomyopathy and tachycardia-dependent left bundle branch block (LBBB). Results were as follows: 1) the recovery time was longer in anterior than in posterior portion of left bundle branch fibers; 2) an high posterior left ventricular point was directly activated via posterior left bundle branch fibers; 3) the directly activated left ventricular zone was too small and relatively too late excited in respect of the right interventricular septum, from which the stimulus reached the left septum, to mask the LBBB electrocardiographic pattern; 4) in the presence of tachycardia-dependent LBBB the duration of left ventricular endocardial activation was about twice (62 msec) that found in the absence of tachycardia-dependent LBBB (28 msec).