Phonocardiographic Studies on Hypertensive Part Ⅱ Phonocardiogram of the Hypertensive by Inhalation of Amyl-Nitrite

PCG and ECG using Amyl-Nitrite were studied in 74 cases of the hypertensive with maximum blood pressure more than 150 mmHg or minimum blood pressure more than 90 mmHg. Twenty five cases of the health were chosen as control. The following results were obtained. 1) Blood pressure showed the lowest near 15 sec after inhalation of Amyl-Nitrite and puls rate was the most markedly increased near 30 sec after. The same results were found in the health. At the period of manifestations in function of` the Amyl-Nitrite, were not found significant differences with maximum, minimum and mean blood pressure measured before ihalation. 2) Duration of the first sound was tend to prolong in the hypertensive (0.076±0.020sec), less prolonged in the health (0.065±0.016 sec). This prolongation was not correlated with maximum and minimum blood pressuse measured before inhalation. 3) Cases showed absolute shortening of the QⅡ interval were increased in the hypertensive. Those shortenings were correlated with LVH. As QII interval was shortened as QⅡ/QT. ratio was decreased. 4) Protodiastolic gallop sound (accentuation of the third heart sound) became significant after inhalation in the hypertensive, and was correlated with LVH. 5) Atrial gallop sound (accentuation of the atrial sound) was accentuated after inhalation in the hypertensive, too. This fact was in discordance with the old reports. The accentuation was connected with LVH. 6) Duration of apical systolic murmur was prolonged in the hypertensive lasting 60 sec after inhalation, and it's amplitude was increased. Some cases showed a new murmur after inhalation. 7) Increase of the amplitude was correlated with ST-T change and accentuation of atrial gallop sound. However, mechanism of Amyl-Nitrite for the accentuation of murmur remained uncertain.