Ventricular pacing inhibition by oversensing due to diaphragmatic myopotential during deep inspiration

AbstractAn 80-year-old man, who had dilated cardiomyopathy with right ventricular (RV) dilatation, underwent implantable cardioverter defibrillator (ICD) implantation for advanced atrioventricular block and primary prevention of sudden cardiac death. Tined and screw-in leads were placed on the right atrial appendage and RV apex, respectively. Ventricular pacing inhibition was detected after surgery due to oversensing by diaphragmatic myopotential occurring only during deep inspiration. We performed re-surgery and switched the screw-in lead for a tined lead. The diaphragmatic myopotential decreased, thereby improving oversensing by diaphragmatic myopotential and ventricular pacing inhibition. It might be beneficial to use a tined lead when placing the ventricular lead at the RV apex for implantation of a pacemaker or ICD if oversensing of diaphragmatic myopotential is observed using a screw-in lead.<Learning objective: Oversensing due to diaphragmatic myopotential is rarely observed. However if it occurs, it becomes a critical problem, which causes pacemaker inhibition or inappropriate ICD shock. However, the method of preventing this problem is unknown. In this case, we demonstrated that a tined-lead may be useful for the prevention of oversensing by diaphragmatic myopotential.

A scoring evaluation for the practical introduction of guideline‐directed medical therapy in heart failure patients

Abstract Aims The guideline‐directed medical therapy (GDMT) has been recommended for heart failure (HF) with reduced ejection fraction (HFrEF) based on the accumulating clinical evidence. However, it is difficult to implement all the trial‐proven medications for every patient in the real world. Methods and results A simple GDMT score was created, according to the combination of GDMT drugs (renin–angiotensin system inhibitors, beta‐blockers, mineralocorticoid receptor antagonists, and sodium–glucose transporter 2 inhibitors) administration and their dosage (0–9 points). Its impact on the prognosis of HF patients was investigated. Admitted HF patients [HFrEF and HF with mildly reduced ejection fraction (HFmrEF), n = 1054] were retrospectively analysed (excluding those with in‐hospital death and dialysis). A simple GDMT score ≥5, but not the number of medications, was significantly associated with a reduction of all‐cause death, HF readmission, and composite outcome (HF readmission and all‐cause death) (P < 0.001). Subgroup analysis showed that almost all groups with a simple GDMT score of 5 or higher had a better prognosis. Conclusions The developed simple GDMT score was associated with prognosis in HFrEF and HFmrEF patients. Even if all four drugs cannot be introduced for some reason, a regimen with a simple GDMT score ≥5 may lead to a prognosis in HF patients