Performance of Computed Tomographic Angiography-Based Aortic Valve Area for Assessment of Aortic Stenosis.

Background A total of 40% of patients with severe aortic stenosis (AS) have low-gradient AS, raising uncertainty about AS severity. Aortic valve calcification, measured by computed tomography (CT), is guideline-endorsed to aid in such cases. The performance of different CT-derived aortic valve areas (AVAs) is less well studied. Methods and Results Consecutive adult patients with presumed moderate and severe AS based on echocardiography (AVA measured by continuity equation on echocardiography <1.5 cm2) who underwent cardiac CT were identified retrospectively. AVAs, measured by direct planimetry on CT (AVACT) and by a hybrid approach (AVA measured in a hybrid manner with echocardiography and CT [AVAHybrid]), were measured. Sex-specific aortic valve calcification thresholds (≥1200 Agatston units in women and ≥2000 Agatston units in men) were applied to adjudicate severe or nonsevere AS. A total of 215 patients (38.0% women; mean±SD age, 78±8 years) were included: normal flow, 59.5%; and low flow, 40.5%. Among the different thresholds for AVACT and AVAHybrid, diagnostic performance was the best for AVACT <1.2 cm2 (sensitivity, 85%; specificity, 26%; and accuracy, 72%), with no significant difference by flow status. The percentage of patients with correctly classified AS severity (correctly classified severe AS+correctly classified moderate AS) was as follows; AVA measured by continuity equation on echocardiography <1.0 cm2, 77%; AVACT <1.2 cm2, 73%; AVACT <1.0 cm2, 58%; AVAHybrid <1.2 cm2, 59%; and AVAHybrid <1.0 cm2, 45%. AVACT cut points of 1.52 cm2 for normal flow and 1.56 cm2 for low flow, provided 95% specificity for excluding severe AS. Conclusions CT-derived AVAs have poor discrimination for AS severity. Using an AVACT <1.2-cm2 threshold to define severe AS can produce significant error. Larger AVACT thresholds improve specificity.

Assessment of the 2017 AHA/ACC/HRS Guideline Recommendations for Implantable Cardioverter-Defibrillator Implantation in Cardiac Sarcoidosis.

BACKGROUND: Implantable cardioverter-defibrillators are used to prevent sudden cardiac death in patients with cardiac sarcoidosis. The most recent recommendations for implantable cardioverter-defibrillator implantation in these patients are in the 2017 American Heart Association/American College of Cardiology/Heart Rhythm Society Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death. These recommendations, based on observational studies or expert opinion, have not been assessed. We aimed to assess them. METHODS: We performed a large retrospective cohort study of patients with biopsy-proven sarcoidosis and known or suspected cardiac sarcoidosis that underwent cardiovascular magnetic resonance imaging. Patients were followed for a composite end point of significant ventricular arrhythmia or sudden cardiac death. The discriminatory performance of the Guideline recommendations was tested using time-dependent receiver operating characteristic analyses. The optimal cutoff for the extent of late gadolinium enhancement predictive of the composite end point was determined using the Youden index. RESULTS: In 290 patients, the class I and IIa recommendations identified all patients who experienced the composite end point during a median follow-up of 3.0 years. Patients meeting class I recommendations had a significantly higher incidence of the composite end point than those meeting class IIa recommendations. Left ventricular ejection fraction (LVEF) >35% with >5.7% late gadolinium enhancement on cardiovascular magnetic resonance imaging was as sensitive as and significantly more specific than LVEF >35% with any late gadolinium enhancement. Patients meeting 2 class IIa recommendations, LVEF >35% with the need for a permanent pacemaker and LVEF >35% with late gadolinium enhancement >5.7%, had high annualized event rates. Excluding 2 class IIa recommendations, LVEF >35% with syncope and LVEF >35% with inducible ventricular arrhythmia, resulted in improved discrimination for the composite end point. CONCLUSIONS: We assessed the Guideline recommendations for implantable cardioverter-defibrillator implantation in patients with known or suspected cardiac sarcoidosis and identified topics for future research.

Computed tomography (CT) assessment of the membranous septal anatomy prior to transcatheter aortic valve replacement (TAVR) with the balloon-expandable SAPIEN 3 valve.

OBJECTIVES: The lower limit of the membranous septum (MS) is considered an anatomic landmark for the emergence of the Bundle of His into the left ventricle. Computed tomography (CT) assessment of MS anatomy may provide useful information about the risk of conduction abnormalities following transcatheter aortic valve replacement (TAVR). METHODS AND RESULTS: The study included 102 consecutive patients undergoing TAVR with the Edwards Sapien 3 (S3) valve. Using pre-TAVR CT and post-procedure angiography we evaluated for the presence of calcium in the left ventricular outflow tract (LVOT), calcium depth (CD), implantation depth (ID) and MS length. The MS length minus the prosthesis ID was calculated (Delta MSID). Outcomes included new left bundle branch block (LBBB) or permanent pacemaker (PPM) within 30days. Seventeen patients (17%) received a PPM and 28 (27%) developed new LBBB following TAVR. Mean (±SD) MS length and delta MSID were 7.5mm (2) and 0.9mm (4.5), respectively. Twenty-one patients (20%) had calcium in the device landing zone and the mean (SD) CD was 6.8mm (±4). Calcium in the device landing zone (37% versus 16%, p=0.02) and implantation depth (6mm (4-8) versus 4mm (4-5), p=0.02) predicted new conduction abnormalities after TAVR. CONCLUSIONS: The presence of calcium in the device landing zone is associated with increased risk of conduction abnormalities after TAVR with S3. In such cases, a more aortic deployment of the prosthesis may be warranted.