Masaki Tsukamoto

Systolic Outward Motion of the Left Ventricular Apical Wall as Detected by Magnetic Resonance Tagging in Patients with Apical Hypertrophic Cardiomyopathy

Patients with apical hypertrophic cardiomyopathy (APH) associated with paradoxic jet flow (ie, diastolic flow away from the apex) may gradually develop an apical aneurysm, which often leads to arrhythmia and mural thrombus formation. We observed systolic outward motion of the left ventricular apical myocardium in patients with APH using a magnetic resonance tagging procedure and examined the relationship of the outward motion to echocardiographic and scintigraphic findings and to cardiac events. Systolic displacement of the myocardial tags of the apical region perpendicular to the long axis in the 4-chamber view was recorded in 31 patients with APH. Of these patients, 14 showed no outward movement of tags (group A), and 17 showed outward movement (group B). In group B, apical hypertrophy was more severe (35 +/- 7 mm vs. 29 +/- 6 mm, p < 0.05), paradoxic jet flow was more frequent (64% vs. 14%, p < 0.05) and the defect score in I-123-beta-methyliodophenylpentadecanoic acid scintigraphy was higher (2.1 +/- 0.7 vs. 1.3 +/- 0.7, p < 0.01). During a mean follow-up period of 55 months, only 1 patient experienced paroxysmal atrial fibrillation in group A. In group B, 1 patient died suddenly, 1 was admitted to hospital because of congestive heart failure, 2 developed angina pectoris, 2 exhibited non-sustained ventricular tachycardia, and 1 showed multifocal premature ventricular contraction; in these 7 patients the outward movement was greater than in the 10 patients in Group B who had no cardiac events (1.00 +/- 0.59 vs. 0.52 +/- 0.40, p < 0.05). Hence, our results show that outward tag displacement is frequently associated with severe apical hypertrophy, paradoxic jet flow, apical ischemia, and cardiac events. The tagging method may be useful in assessing the severity of APH and predicting the occurrence of cardiac events at an early stage.

Slow-fast Form of Atrioventricular Nodal Reentrant Tachycardia with Unusual Retrograde Activation in the Right Atrium —Possible Conduction Disturbance across the Tendon of Todaro Related to the Genesis of Positive Component of Biphasic Retrograde P Wave—

We report a rare case of slow‐fast form of atrioventricular nodal reentrant tachycardia with delayed activation in the low septal right atrium (His bundle area). During supraventricular tachycardia (SVT), electrocardiogram showed “pseudo‐positive P waves” in II, III, and aVF leads. SVT was induced by atrial extrastimulus with marked AH prolongation (i.e., jump phenomenon). Ventricular pacing showed a decremental retrograde conduction without jump phenomenon. Double atrial potentials were observed in the His bundle area during SVT and during ventricular pacing. The first electrogram of these split potentials, which was the earliest activation during SVT and during ventricular pacing, showed a dull and small deflection, whereas the second electrogram was sharp and clear. The interval of these discrete potentials was 70 msec during SVT. After a standard slow pathway ablation, SVT could never be induced by any programmed stimuli. It was concluded that in this case, the conduction disturbance across the tendon of Todaro was likely to cause the delayed atrial activation in the His bundle area, which created the pseudo‐positive (biphasic. retrograde P wave.

Echocardiographically documented acute aortic insufficiency induced by Amplatz left guide catheter

This paper examines a case of sudden systolic pressure fall, tachycardia, low pulse pressure, and high pulmonary artery wedge pressure due to acute aortic insufficiency which was induced by an Amplatz left (AL-1) guide catheter used for better guide support during percutaneous transluminal coronary angioplasty of the right coronary artery. AL guide catheters can cause acute aortic insufficiency, of which practitioners should be aware when sudden hemodynamic collapse occurs. (Int J Cardiovasc Intervent 2000; 3: 237-239)