Evidence of subannular and left ventricular morphological differences in patients with bicuspid versus tricuspid aortic valve stenosis: magnetic resonance imaging-based analysis.

Objectives: Prospective analysis of left ventricular (LV) morphological/functional parameters in patients with bicuspid versus tricuspid aortic valve (TAV) stenosis undergoing aortic valve replacement (AVR) surgery. Methods: A total of 190 consecutive patients with BAV ( n = 154) and TAV stenosis ( n = 36) (mean age 61 ± 8 years, 65% male) underwent AVR ± concomitant aortic surgery from January 2012 through May 2015. All patients underwent preoperative cardiac magnetic resonance imaging in order to evaluate: (i) left ventricular outflow tract (LVOT) dimensions, (ii) length of anterior mitral leaflet (AML), (iii) end-systolic and end-diastolic LV wall thickness, (iv) LV area, (v) LV end-systolic and end-diastolic diameters (LVESD, LVEDD), (vi) LV end-diastolic and end-systolic volumes (LVEDV, LVESV) and (vii) maximal diameter of aortic root. These parameters were compared between the two study groups. Results: The LVOT diameter was significantly larger in BAV patients (21.7 ± 3 mm in BAV vs 18.9 ± 3 mm in TAV, P < 0.001). Moreover, BAV patients had significantly longer AML (24 ± 3 mm in BAV vs 22 ± 4 mm in TAV, P = 0.009). LVEDV and LVESV were significantly larger in BAV patients (LVEDV: 164.9 ± 68.4 ml in BAV groups vs 126.5 ± 53.1 ml in TAV group, P = 0.037; LVESV: 82.1 ± 57.9 ml in BAV group vs 52.9 ± 25.7 ml in TAV group, P = 0.008). A strong linear correlation was found between LVOT diameter and aortic annulus diameter in BAV patients ( r = 0.7, P < 0.001), whereas significantly weaker correlation was observed in TAV patients ( r = 0.5, P = 0.006, z = 1.65, P = 0.04). Presence of BAV morphology was independently associated with larger LVOT diameters (OR 9.0, 95% CI 1.0-81.3, P = 0.04). Conclusions: We found relevant differences in LV morphological/functional parameters between BAV and TAV stenosis patients. Further investigations are warranted in order to determine the cause of these observed differences.

Morphologic and Functional Markers of Aortopathy in Patients With Bicuspid Aortic Valve Insufficiency Versus Stenosis.

BACKGROUND: Bicuspid aortic valve (BAV)-associated aortopathy is heterogeneous and still insufficiently defined. We prospectively analyzed the morphologic and functional variables of aortopathy in patients undergoing operations for BAV insufficiency (BAV-AI) vs stenosis (BAV-AS). METHODS: A total of 172 consecutive patients (71% male, 59 ± 10 years) underwent aortic valve replacement with or without proximal aortic operation for BAV-AS (n = 137), and BAV-AI (n = 35) from January 2012 through December 2014. All patients underwent preoperative cardiac magnetic resonance imaging to evaluate morphologic and functional variables of the aortic root. Magnetic resonance imaging data were used to guide sampling of aortic tissue intraoperatively (ie, from the area where flow jet impacts on the aortic wall [jet sample] and the opposite aortic wall [control sample]). Aortic wall lesions were graded based on the histologic sum score (range, 0 to 21). Expression and severity of aortopathy were quantified by means of proximal aortic phenotype, indexed aortic diameters, and a sum score. RESULTS: Cross-sectional aortic diameters were significantly larger in the BAV-AI group vs the BAV-AS group (47 ± 8 mm vs 41 ± 8 mm, p = 0.001). Moreover, root dilatation phenotype was more frequent in the BAV-AI group (27% vs 6%, p = 0.01) and was associated with a significantly larger aortic annulus diameter (32 ± 3 mm vs 27 ± 3 mm, p < 0.001). The histologic sum score was significantly different between the study groups (3.7 ± 2.6 BAV-AI vs 2.5 ± 1.4 BAV-AS, p = 0.03). Logistic regression revealed a significant association between BAV-AI and indexed aortic diameter exceeding 22 mm/m2 (odds ratio, 4.7; p = 0.007). CONCLUSIONS: Our study demonstrates that BAV functional phenotype correlates significantly with the expression and severity of bicuspid aortopathy.

Subannular perforation of left ventricular outflow tract associated with transcatheter valve implantation: pathophysiological background and clinical implications.

OBJECTIVES: Perforation of the subannular left ventricular outflow tract (LVOT) represents an uncommon but almost invariably fatal transcatheter aortic valve implantation (TAVI)-associated complication. The risk factors to predict the occurrence of this devastating complication, particularly in relation to specific LVOT anatomy, have not yet been systematically analysed. We aimed to evaluate the pathophysiological background and possible risk factors for the occurrence of subannular LVOT perforation. METHODS: A total of 6 (0.7%) consecutive patients (78.8 ± 3.3 years, 83% women) with subannular LVOT perforation complicating TAVI procedure were identified from our institutional TAVI registry, including 900 consecutive patients who underwent TAVI procedure at a single institution between January 2009 and July 2015. Only patients with an intraoperatively confirmed LVOT perforation were included. RESULTS: The computed tomography (CT)-guided analysis of aortic root/LVOT morphology revealed subannular calcification in close proximity of the anatomically weakest region of muscular LVOT (i.e. in the region of the muscular LVOT between the left fibrous trigone and the left/right commissure) in 5/6 (83%) patients. Moreover, significant annular asymmetry >20% was present in 4/6 (67%) patients and was combined with a severe asymmetric hypertrophy of muscular LVOT. CONCLUSIONS: Subannular calcification in close proximity of the anatomically unprotected muscular LVOT might represent an important risk factor for the occurrence of subannular LVOT injury. Precise CT-based analysis of patient-specific aortic root anatomy/subannular calcification patterns may be helpful to predict this TAVI-associated complication preoperatively and hence to avoid it in future patients.

Aortopathy in Bicuspid Aortic Valve Stenosis with Fusion of Right-Left versus Right-Non-Coronary Cusps: Are These Different Diseases?

BACKGROUND: The study aim was to prospectively analyze the impact of cusp fusion pattern on aortopathy severity in patients undergoing surgery for bicuspid aortic valve (BAV) stenosis. METHODS: A total of 137 consecutive patients with BAV stenosis (93 males, 44 females; mean age 61 ± 9 years) underwent aortic valve replacement with or without concomitant aortic surgery between January 2012 and March 2015. All patients underwent preoperative cardiac magnetic resonance imaging (cMRI) in order to evaluate morphological/functional parameters of the aortic root. Fusion of the right-left coronary cusps was identified in 99 patients (72%) (R/L group), while the remaining 38 patients (28%) had right-noncoronary cusp fusion (R/N group). cMRI data were used to guide sampling of the proximal aorta during surgery. The expression/severity of aortopathy was quantified by means of proximal aortic phenotype, indexed aortic diameter, and a histological sum-score. RESULTS: There were no significant differences in proximal aortic diameter between the R/L and R/N groups. Moreover, there was no significant difference in the prevalence of distinct aortic phenotypes between the study subgroups. The histological sumscore was comparable between the R/L and R/N groups (2.9 ± 1.5 versus 2.5 ± 1.1, p = 0.2). The angle LV/aorta was significantly larger in the R/L group than in the R/N group (52.1 ± 10.6° versus 45.1 ± 8.5°, p = 0.001). Logistic regression analysis demonstrated the angle LV/aorta and the angle jet/aorta to be predictive of a mid-ascending phenotype. The cusp fusion pattern had no significant impact on the occurrence of aortic phenotype. CONCLUSIONS: The study results demonstrated that cusp fusion morphotype has no significant impact on the expression and severity of bicuspid aortopathy in patients undergoing surgery for BAV stenosis.

Functional Aortic Root Parameters and Expression of Aortopathy in Bicuspid Versus Tricuspid Aortic Valve Stenosis.

BACKGROUND: The correlation between bicuspid aortic valve (BAV) disease and aortopathy is not fully defined. OBJECTIVES: This study aimed to prospectively analyze the correlation between functional parameters of the aortic root and expression of aortopathy in patients undergoing surgery for BAV versus tricuspid aortic valve (TAV) stenosis. METHODS: From January 1, 2012 through December 31, 2014, 190 consecutive patients (63 ± 8 years, 67% male) underwent aortic valve replacement ± proximal aortic surgery for BAV stenosis (n = 137, BAV group) and TAV stenosis (n = 53, TAV group). All patients underwent pre-operative cardiac magnetic resonance imaging to evaluate morphological/functional parameters of the aortic root. Aortic tissue was sampled during surgery on the basis of the location of eccentric blood flow contact with the aortic wall, as determined by cardiac magnetic resonance (i.e., jet sample and control sample). Aortic wall lesions were graded using a histological sum score (0 to 21). RESULTS: The largest cross-sectional aortic diameters were at the mid-ascending level in both groups and were larger in BAV patients (40.2 ± 7.2 mm vs. 36.6 ± 3.3 mm, respectively, p < 0.001). The histological sum score was 2.9 ± 1.4 in the BAV group versus 3.4 ± 2.6 in the TAV group (p = 0.4). The correlation was linear and comparable between the maximum indexed aortic diameter and the angle between the left ventricular outflow axis and aortic root (left ventricle/aorta angle) in both groups (BAV group: r = 0.6, p < 0.001 vs. TAV group r = 0.45, p = 0.03, z = 1.26, p = 0.2). Logistic regression identified the left ventricle/aorta angle as an indicator of indexed aortic diameter >22 mm/m(2) (odds ratio: 1.2; p < 0.001). CONCLUSIONS: Comparable correlation patterns between functional aortic root parameters and expression of aortopathy are found in patients with BAV versus TAV stenosis.

The fate of mild-to-moderate proximal aortic dilatation after isolated aortic valve replacement for bicuspid aortic valve stenosis: a magnetic resonance imaging follow-up study†.

OBJECTIVES: The treatment of mild-to-moderate aortic dilatation at the time of aortic valve replacement (AVR) in patients with bicuspid aortic valve (BAV) disease is still controversial. We aimed to estimate late progression of aortopathy in patients who underwent isolated AVR for BAV stenosis with concomitant proximal aortic dilatation of ≥40 mm. METHODS: The review of our institutional BAV database (n = 510) revealed a subgroup of 96 consecutive BAV patients (57 ± 10 years, 78% male) with BAV stenosis and concomitant ascending aortic dilatation of ≥40 mm [i.e. as defined by magnetic resonance imaging (MRI)/computed tomography (CT)], who underwent isolated AVR from 1995 to 2006. Aortic diameters were quantified by preoperative MRI/CT in all patients (i.e. all cases without MRI/CT were excluded). Moreover, we excluded all cases of simultaneous aortic surgery. MRI/CT follow-up (855 patient-years) was obtained in 83 (87%) patients. Study end-points were progression of proximal aortic diameters (mm/patient-year) and prevalence of aortic events (sudden death, aortic dissection and aortic surgery). RESULTS: MRI/CT follow-up (mean 10.3 ± 3.8 years post-AVR) revealed no significant progress of maximal cross-sectional aortic diameters (i.e. 46.4 ± 4.4 mm pre-AVR vs 46.9 ± 4.6 mm post-AVR, P = 0.1). Aortic diameters were identical in 54 (65%) patients. The mean progression rate of maximal cross-sectional aortic diameter was 0.09 mm/patient-year for the whole study cohort, whereas diameter increase of ≥5 mm was revealed in 1 (1%) patient. No aortic dissection occurred. Five (5%) patients underwent redo aortic surgery for aneurysm, whereas 3 of them had aortic diameters identical to pre-AVR. CONCLUSIONS: Mild-to-moderate ascending aortic dilatation remains stable in most BAV patients who underwent isolated AVR surgery for aortic valve stenosis at least 10-year post-AVR.

Aortopathy in patients with bicuspid aortic valve stenosis: role of aortic root functional parameters.

OBJECTIVES: We prospectively examined functional characteristics of the aortic root and transvalvular haemodynamic flow in order to define factors associated with the severity of aortopathy in patients undergoing surgery for bicuspid aortic valve (BAV) stenosis. METHODS: A total of 103 consecutive patients with BAV stenosis (mean age 61 ± 9 years, 66% male) underwent aortic valve replacement ± concomitant aortic surgery from January 2012 through March 2014. All patients underwent preoperative cardiac magnetic resonance imaging (MRI) in order to evaluate the systolic transvalvular flow and the following functional parameters: (i) angulation between the left ventricular outflow axis and the aortic root, (ii) geometrical orientation of residual aortic valve orifice and (iii) BAV cusp fusion pattern. MRI data were used to guide sampling of the ascending aorta during surgery [i.e. jet-sample from the area where the flow-jet impacts on the aortic wall and control sample from the opposite aortic wall (obtained from the aortotomy site)]. Aortopathy was quantified by means of a histological sum-score (0 to 21+) in each sample. RESULTS: A significant correlation was found between histological sum-score in the jet-sample and the angle between the LV outflow axis and the aortic root (r = 0.6, P = 0.007). Moreover, there was a linear correlation between proximal aortic diameter and the angle between systolic flow-jet and ascending aortic wall (r = 0.5, P = 0.006). Logistic regression identified the angle between the LV outflow axis and the aortic root (OR 1.1, P = 0.04) and the angle between the flow-jet and the aortic wall (OR 1.2, P = 0.001) as independent predictors of an indexed proximal aortic diameter ≥22 mm/m(2). CONCLUSIONS: Functional parameters of the aortic root may be used to predict the severity of aortopathy in patients with BAV stenosis, and may be useful in predicting future risk of aortic disease in such patients.

Correlation between systolic transvalvular flow and proximal aortic wall changes in bicuspid aortic valve stenosis.

OBJECTIVES: The purpose of this study was to analyse the correlation between preoperative systolic transvalvular flow patterns and proximal aortic wall lesions in patients undergoing surgery for bicuspid aortic valve (BAV) stenosis. METHODS: A total of 48 consecutive patients with BAV stenosis (mean age 58 ± 9 years, 65% male) underwent aortic valve replacement (AVR) ± proximal aortic surgery from January 2012 through February 2013. Preoperative cardiac phase-contrast cine magnetic resonance imaging (MRI) assessment was performed in all patients in order to detect the area of maximal flow-induced stress in the proximal aorta. Based on these MRI data, two aortic wall samples (i.e. area of the maximal stress (jet sample) and the opposite aortic wall (control sample)) were collected during AVR surgery. Aortic wall changes were graded based on a summation of seven histological criteria (each scored from 0 to 3). Histological sum score (0-21) was separately calculated and compared between the two aortic samples (i.e. jet sample vs control sample). RESULTS: An eccentric transvalvular flow jet hitting the proximal aortic wall could be identified in all 48 (100%) patients. The mean histological sum score was significantly higher in the jet sample vs control sample areas of the aorta (i.e. 4.1 ± 1.8 vs 2.2 ± 1.5, respectively) (P = 0.02). None of the patients had a higher sum score value in the control sample. CONCLUSIONS: Our study demonstrates a strong correlation between the systolic pattern of the transvalvular flow jet and asymmetric proximal aortic wall changes in patients undergoing AVR for BAV stenosis.

Effect of cardiac resynchronization therapy on the incidence of electrical storm.

BACKGROUND: Hemodynamic improvement from biventricular pacing is well documented; however, its electrophysiologic effects have not been systematically studied. In this study, incidence and risk factors for electrical storm (ES) were investigated in 729 ICD and biventricular defibrillator (CRT-D) heart failure patients. METHODS: 168 consecutive CRT-D and 561 ICD patients were retrospectively analyzed for the occurrence of VT/VF and predisposing factors. Electrical storm was defined as ventricular tachycardia or fibrillation ≥3 times during 24 h. Mean follow-up was 41 months. RESULTS: In 168 CRT-D patients only one patient experienced electrical storm compared to 39 patients out of 561 ICD patients (0.6% vs. 7%, p<0.01). 33% of the patients with electrical storm died within one year. In the CRT-D group 81 patients (48%) developed VT or VF and received at least one appropriate therapy, compared to 281 patients (50%) in the ICD group. Mean ejection fraction was 21.7% in the CRT-D group and 34.7% (p<0.01) in the ICD group. Stratifying the patients according to primary or secondary prevention and ejection fraction demonstrated that VT/VF clusters were significantly associated with ICD indication for secondary prevention, previous myocardial infarction and LVEF<30%. CONCLUSION: The development of electrical storm is accompanied with a highly increased mortality risk even if an ICD/CRT-D is implanted. In CRT-D patients electrical storm is much less common than in ICD patients. Secondary prevention and ejection fraction<30% are predictors of electrical storm. Beside hemodynamic improvements cardiac resynchronization therapy may reduce the arrhythmia burden in heart failure patients.