Effect of Constant vs. Variable Moderate-Intensity Load on Peak Oxygen Uptake in Outpatient Cardiac Rehabilitation.

Background: In outpatient center-based cardiac rehabilitation (O-CBCR), moderate-intensity continuous training (MICT) based on the anaerobic threshold (AT) determined by cardiopulmonary exercise stress testing is recommended. However, it is unclear whether differences in exercise intensity within the MICT domain affect peak oxygen uptake (%peakV̇O2). Methods and Results: We retrospectively evaluated patients who underwent O-CBCR at Japan Community Healthcare Organization Osaka Hospital. Those treated with the constant-load method were designated as Group A (n=38), whereas those treated with the variable-load method were designated as Group B (n=48). Although the change in exercise intensity was significantly greater in Group B by approximately 4.5 W, the change in %peakV̇O2 was not significantly different between groups. Group A had a significantly longer exercise time than Group B (by approximately 4-5 min). No deaths or hospitalizations occurred in either group. The percentage of episodes with exercise cessation was similar between the 2 groups, but the percentage of episodes with load reduction was significantly higher in Group B, mostly because of the increased heart rate. Conclusions: In supervised MICT based on AT, the variable-load method increased exercise intensity more than the constant-load method without severe complications, but did not improve %peakV̇O2.

Subcutaneous-implantable cardioverter defibrillator lead dislodgement in a juvenile catecholamine-induced polymorphic ventricular tachycardia patient.

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a relatively rare inherited arrhythmic disease that causes sudden cardiac death, and is caused by mutations in the cardiac ryanodine receptor (RyR2) or sarcoplasmic reticulum protein calsequestrin 2 gene (CASQ2). A 16-year-old man was diagnosed with CPVT and was implanted with a Subcutaneous-implantable Cardioverter Defibrillator (S-ICD), but defibrillation electrode detachment occurred early after placement. We suspected that a two-incision technique was the possible cause. We also report on changes in surface ECG in remote monitoring of the device. TAKE HOME MESSAGE  Although two-incision techniques are becoming the mainstream method of S-ICD implantation, we should consider that the three-incision technique may be advantageous in highly active patients. Remote monitoring may also be useful for early detection of S-ICD dislodgement.

Acute Myocardial Infarction Due to Coronary Occlusion Caused by a Metastatic Cardiac Tumor Arising from Squamous Cell Lung Cancer: An Evaluation with Three-dimensional Transthoracic Echocardiography.

A 60-year-old man developed acute myocardial infarction from the total occlusion of the right coronary artery via metastatic squamous lung cancer and was treated with percutaneous coronary intervention (PCI). Computed tomography and transthoracic echocardiography (TTE) revealed a metastatic tumor, and three-dimensional TTE was useful for determining the size and location of the tumor in relation to the coronary artery. Six months after PCI, the patient died, and an autopsy confirmed extensive metastasis to the heart and nearby vessels as detected by three-dimensional TTE. Although rare, lung cancer metastasis to the heart may directly occlude the coronary artery.

Blood Pressure Increases Before Pulse Rate During the Nocturnal Period in Hypertensive Patients.

Ambulatory blood pressure monitoring (ABPM) is used for the evaluation of out-of-office blood pressure (BP), however, knowledge concerning the detailed behavior of nocturnal blood pressure (BP) and pulse rate (PR) is limited.A total of 190 participants (64 ± 15 years, 46.3% males) underwent ABPM for diagnosis of hypertension or evaluation of hypertensive therapy. BP and PR were measured automatically by the oscillometric method. From the hourly average ABPM values, the nocturnal time courses (0 AM to 6 AM) of SBP and PR were determined and compared to each other.In general, SBP fell to the lowest level at around midnight and started to increase progressively towards dawn while PR stayed unchanged until 7 AM. Age and gender affected the time course of SBP, most distinctly in the female patients aged ≥ 60 years. The time course of the increase of SBP was very similar in the patients, with BP dipping and non-dipping. The cardiothoracic ratio (CTR) slightly and renal dysfunction modestly facilitated the increase of nocturnal SBP. The nocturnal increase in SBP was not accompanied by an increase of PR in any group or subgroup. The pathophysiology and clinical significance of the early and exclusive increase in nocturnal BP need to be investigated.Average ABPM values in these hypertensive patients showed that BP starts to increase toward dawn without an increase in PR and that this discrepant behavior between BP and RP was most distinct in females 60 or older. The mechanism and clinical significance of such a discordant variation in BP and PR need to be elucidated.