Prevalence and characteristics of coronary artery disease in heart failure with preserved and mid-range ejection fractions: A systematic angiography approach.

BACKGROUND: Guidelines recommend careful screening and treatment of coronary artery disease (CAD) in heart failure with preserved or mid-range ejection fraction (HFpEF/HFmEF). AIM: We aimed to determine the prevalence and characteristics of CAD using a prospective systematic coronary angiography approach. METHODS: A systematic coronary angiography protocol was applied in consecutive patients admitted for HFpEF/HFmEF during a 6-month period in a single centre. History of CAD and results of angiography, including revascularization, were reported. RESULTS: Of the 164 patients with HFpEF/HFmEF who were included, an angiography assessment was applied in 108 (66%) (median age: 79 years [interquartile range: 70-85 years]; 54% were women). In our analysis, 64% (95% confidence interval [CI] 55-73%) of patients had a significant coronary stenosis corresponding to a global CAD prevalence of 80% (95% CI 73-88%). The prevalence of CAD was similar for HFpEF and HFmEF. The left main coronary artery presented a significant stenosis in 6.5% of cases and 39% of patients had a two- or three-vessel disease. The rate of significant coronary stenosis was non-significantly higher in patients with a history of CAD. Patients with HFpEF/HFmEF with and without CAD did not differ in clinically meaningful ways, in terms of symptoms or laboratory and echocardiography results. This strategy led to complete revascularization in 36% of patients with significant stenosis and in 23% of all patients with HFpEF/HFmEF. CONCLUSIONS: Our study differs from others in that we used a systematic angiography approach. The results suggest a much higher prevalence of CAD in HFpEF/HFmEF than previously reported and should encourage clinicians to aggressively identify this co-morbidity.

Vagal Reactions during Cryoballoon-Based Pulmonary Vein Isolation: A Clue for Autonomic Nervous System Modulation?

Although paroxysmal atrial fibrillation (AF) is known to be initiated by rapid firing of pulmonary veins (PV) and non-PV triggers, the crucial role of cardiac autonomic nervous system (ANS) in the initiation and maintenance of AF has long been appreciated in both experimental and clinical studies. The cardiac intrinsic ANS is composed of ganglionated plexi (GPs), located close to the left atrium-pulmonary vein junctions and a vast network of interconnecting neurons. Ablation strategies aiming for complete PV isolation (PVI) remain the cornerstone of AF ablation procedures. However, several observational studies and few randomized studies have suggested that GP ablation, as an adjunctive strategy, might achieve better clinical outcomes in patients undergoing radiofrequency-based PVI for both paroxysmal and nonparoxysmal AF. In these patients, vagal reactions (VR) such as vagally mediated bradycardia or asystole are thought to reflect intrinsic cardiac ANS modulation and/or denervation. Vagal reactions occurring during cryoballoon- (CB-) based PVI have been previously reported; however, little is known on resulting ANS modulation and/or prevalence and significance of vagal reactions during PVI with the CB technique. We conducted a review of prevalence, putative mechanisms, and significance of VR during CB-based PVI.

Electromyographic monitoring for prevention of phrenic nerve palsy in second-generation cryoballoon procedures.

BACKGROUND: Electromyography-guided phrenic nerve (PN) monitoring using a catheter positioned in a hepatic vein can aid in preventing phrenic nerve palsy (PNP) during cryoballoon ablation for atrial fibrillation. We wanted to evaluate the feasibility and efficacy of PN monitoring during procedures using second-generation cryoballoons. METHODS AND RESULTS: This study included 140 patients (43 women) in whom pulmonary vein isolation was performed using a second-generation cryoballoon. Electromyography-guided PN monitoring was performed by pacing the right PN at 60 per minute and recording diaphragmatic compound motor action potential (CMAP) via a quadripolar catheter positioned in a hepatic vein. If a 30% decrease in CMAP amplitude was observed, cryoapplication was discontinued with forced deflation to avoid a PNP. Monitoring was unfeasible in 8 of 140 patients (5.7%), PNP occurred in 1. Stable CMAP amplitudes were achieved before ablation in 132 of 140 patients (94.3%). In 18 of 132 patients (13.6%), a 30% decrease in CMAP amplitude occurred and cryoablation was discontinued. Each time, recovery of CMAP amplitude took <60 s. In 9 of 18 cases, a second cryoapplication in the same pulmonary vein was safely performed. We observed no PNP or complication related to electromyography-guided PN monitoring. CONCLUSIONS: Electromyography-guided PN monitoring using a catheter positioned in a hepatic vein seems feasible and effective to prevent PNP during cryoballoon ablation using second-generation cryoballoon.