Computational quantitative flow ratio to assess functional severity of coronary artery stenosis.

Background Computational quantitative flow ratio (QFR) based on 3-dimensional quantitative coronary angiography (3D QCA) analysis offers the opportunity to assess the significance of coronary artery disease (CAD) without using an invasive pressure wire or inducing hyperemia. This study aimed to evaluate the diagnostic performance of QFR compared to wire-based fractional flow reserve (FFR) and to validate the previously reported QFR cut-off value of >0.90 to safely rule out functionally significant CAD. Methods QFR was retrospectively derived from standard-care coronary angiograms. Correlation and agreement of fixed-flow QFR (fQFR) and contrast-flow QFR (cQFR) models with invasive wire-based FFR was calculated. Diagnostic performance of QFR was evaluated at different QFR cut-off values defining significant CAD (FFR ≤ 0.80). Results 101 vessels in 96 patients who underwent FFR were studied. Mean FFR was 0.87 ±â€¯0.08 and 21 of 101 (21%) vessels had an FFR ≤ 0.80. Correlation of fQFR and cQFR with FFR was r = 0.71 (p < 0.001) and r = 0.70 (p < 0.001), respectively. Sensitivity and specificity were 57% and 93% for fQFR and 67% and 96% for cQFR at a QFR cut-off value >0.80 defining non-significant CAD, respectively. fQFR > 0.90 was present in 34 (34%) and cQFR > 0.90 in 39 (39%) vessels. For both QFR models, none of the vessels with QFR > 0.90 had an FFR ≤ 0.80. Conclusions QFR appears to be a safe and effective gatekeeper to wire-based FFR when applying a QFR threshold of >0.90 to rule out significant CAD. Further prospective research is required to establish QFR in the real-life setting of functional CAD assessment in the catheterization laboratory.

Atrial fibrillation modifies the association between pulmonary artery wedge pressure and left ventricular end-diastolic pressure.

AIMS: During right heart catheterization, pulmonary artery wedge pressure (PAWP) is often assumed to reflect left ventricular filling pressure. We sought to determine the impact of atrial fibrillation (AF) on the relationship between PAWP and left ventricular filling pressure, as measured by left ventricular end-diastolic pressure (LVEDP). METHODS AND RESULTS: We performed simultaneous left and right heart catheterization in 123 patients (mean age 69 years, 28% with AF) referred for suspicion of pulmonary hypertension (PH). The correlation between PAWP and LVEDP was moderate (R2 = 0.42). The relationship between PAWP and LVEDP was modified by heart rhythm (P for interaction <0.01). In sinus rhythm, PAWP underestimated LVEDP (Bland-Altman mean difference: -2.96 mmHg, limits of agreement 6.6 to -12.5; R2 = 0.54), whereas in AF, PAWP overestimated LVEDP (Bland-Altman mean difference: 4.76 mmHg; limits of agreement: 12.2 to -3.3; R2 = 0.58). These differences impacted the differentiation between pre- and post-capillary PH, dependent on the use of either PAWP or LVEDP. In AF, post-capillary PH based on PAWP would have been classified as pre-capillary PH in 35% of patients if based on LVEDP. The opposite is true for sinus rhythm where 31% of pre-capillary PH based on PAWP would have been classified as post-capillary PH if based on LVEDP. CONCLUSION: The relationship between PAWP and LVEDP varies by heart rhythm, with PAWP being higher than LVEDP among AF patients and lower than LVEDP among patients in sinus rhythm. Rhythm status and influences on the PAWP-LVEDP relationship should be considered when distinguishing between pre-capillary and post-capillary PH.

Emergency transcatheter aortic valve implantation in patients with severe aortic regurgitation and a left ventricle assist device: A case report and systematic review.

BACKGROUND: Cardiogenic shock due to severe aortic regurgitation in patients with left ventricle assist devices is a life threatening condition. Here, we consider transcatheter aortic valve implantation as a treatment option. METHODS AND RESULTS: A patient with a left ventricle assist device was presented to us with cardiogenic shock due to severe aortic regurgitation. We successfully implanted a transcatheter aortic valve in emergency setting. The patient recovered and underwent cardiac transplantation three months afterwards. We performed a systematic literature review and identified 10 cases of patients with a left ventricle assist device undergoing transcatheter aortic valve implantation. In these cases, there was no procedural related mortality reported. In four (40%) patients, transcatheter aortic valve implantation resulted in significant paravalvular aortic regurgitation. In two of these cases it was due to migration of the valve towards the left ventricle. CONCLUSIONS: Our case report and review of literature suggests that transcatheter aortic valve implantation is a feasible and lifesaving treatment option for left ventricle assist device patients presenting with severe aortic regurgitation.