Faculty Bibliography

OBJECTIVES/OBJECTIVE:The aim of this study was to clarify the dynamics of the mitral annulus throughout the cardiac cycle and its relevance to transcatheter mitral valve replacement (TMVR) sizing and case selection. BACKGROUND:Limited data are available regarding the relevance of mitral annular (MA) and neo-left ventricular outflow tract (LVOT) dynamics in the overall population presenting with significant mitral valve disease. METHODS:Patients attending a combined surgical-transcatheter heart valve clinic for severe symptomatic mitral valve disease were assessed using multiphase computed tomography. The relative influence of MA and neo-LVOT dynamics to TMVR case selection was studied. RESULTS:A total of 476 patients with significant mitral valve disease were evaluated. In 99 consecutive patients with severe mitral regurgitation, a 10-phase assessment showed that the mitral annulus was on average largest in late systole. On comparing maximal MA dimension with late systolic dimension, TMVR size assignment changed in 24.2% of patients. If the average MA perimeter was used to determine sizing, 48.5% were excluded because of MA dimension being too large; in a multiphase assessment of the neo-LVOT, an additional 16.2% were excluded on the basis of neo-LVOT dimension. In an expanded series of 312 consecutive patients, selection protocol influenced anatomical exclusion: a manufacturer-proposed early systolic approach excluded 69.2% of patients, whereas a late systolic approach excluded 82.7% of patients, the vast majority because of large mitral annuli. CONCLUSIONS:Contemporary TMVR can treat only a minority of patients with severe mitral regurgitation, principally because of limitations of large MA dimension.

OBJECTIVES/OBJECTIVE:To describe the use of orbital atherectomy to prepare iliofemoral vessels for large-bore access prior to transcatheter aortic valve replacement (TAVR). BACKGROUND:Transfemoral (TF)-TAVR has been shown to be at least equivalent to surgery. Nevertheless, many patients do not qualify for the TF approach due to severe iliofemoral occlusive disease. The use of an atherectomy device in order to facilitate TF-TAVR has only been reported in case reports. METHODS:We performed 1000 TAVR procedures from June 2017 to October 2019. Patient demographics, procedural characteristics, computed tomography characteristics, and short-term outcomes were recorded. Hostile access was defined as luminal size <5 mm, or <5.5 mm along with the presence of >270° calcification. The primary endpoint was the ability to successfully deliver a transcatheter valve via the intended pretreated access site. RESULTS:During the study period, 6 subjects (0.6%) required alternative access and 68 patients (6.8%) were considered to have a hostile iliofemoral anatomy that required vessel preparation prior to TAVR. Forty-eight patients (70.6%) had angioplasty only and 20 patients (29.4%) required atherectomy and angioplasty. Out of 20 patients treated with atherectomy, successful TF delivery of the valve was achieved in 19 patients (95%). There was no in-hospital mortality or stroke. There were no perforations. One subject required placement of a self-expandable stent due to severe dissection. CONCLUSION/CONCLUSIONS:Orbital atherectomy used for vessel preparation is a safe and very effective technique to facilitate TF-TAVR in patients with hostile peripheral anatomy.

Background/UNASSIGNED:Acquired pulmonary vein stenosis (PVS) is an infrequent complication of atrial fibrillation ablation that is often misdiagnosed due to predominant respiratory symptoms. It can result in pulmonary venous hypertension, with varying presentations, ranging from shortness of breath to haemoptysis. Case summary/UNASSIGNED:We report two patients with a history of paroxysmal atrial fibrillation treated with radiofrequency ablation and pulmonary vein (PV) isolation, who subsequently developed PVS. Case 1 initially presented with indolent symptoms of shortness of breath and cough. He was initially diagnosed with and treated for pneumonia. In contrast, Case 2 presented with massive haemoptysis, requiring intubation and intensive care unit admission. Both patients were eventually diagnosed with PVS by computed tomography. They were treated with PV angioplasty and stenting. Discussion/UNASSIGNED:While previously limited to the congenital heart disease population, PVS is occurring more frequently now in adult patients as a complication of ablation procedures. It is most effectively treated with angioplasty and stent implantation but has a high rate of recurrence.

BACKGROUND:Patients with renal insufficiency have poor short-term outcomes after transcatheter aortic valve replacement (TAVR). METHODS:Retrospective chart review identified 575 consecutive patients not on hemodialysis who underwent TAVR between September 2014 and January 2017. Outcomes were defined by VARC-2 criteria. Primary outcome of all-cause mortality was evaluated at a median follow-up of 811 days (interquartile range 125-1,151). RESULTS:Preprocedural glomerular filtration rate (GFR) was ≥60 ml/min in 51.7%, 30-60 ml/min in 42.1%, and < 30 ml/min in 6.3%. Use of transfemoral access (98.8%) and achieved device success (91.0%) did not differ among groups, but less contrast was used with lower GFR (23 ml [15-33], 24 ml [14-33], 13 ml [8-20]; p < .001). Peri-procedural stroke (0.7%, 2.1%, 11.1%; p < .001) was higher with lower GFR. Core lab analysis of preprocedural computed tomography scans of patients who developed a peri-procedural stroke identified potential anatomic substrate for stroke in three out of four patients with GFR 30-60 ml/min and all three with GFR <30 ml/min (severe atheroma was the most common subtype of anatomical substrate present). Compared to GFR ≥60 ml/min, all-cause mortality was higher with GFR 30-60 ml/min (HR 1.61 [1.00-2.59]; aHR 1.61 [0.91-2.83]) and GFR <30 ml/min (HR 2.41 [1.06-5.48]; aHR 2.34 [0.90-6.09]) but not significant after multivariable adjustment. Follow-up echocardiographic data, available in 63%, demonstrated no difference in structural heart valve deterioration over time among groups. CONCLUSIONS:Patients with baseline renal insufficiency remain a challenging population with poor long-term outcomes despite procedural optimization with a transfemoral-first and an extremely low-contrast approach.

Left ventricular outflow tract (LVOT) obstruction in hypertrophic cardiomyopathy (HCM) is often caused by systolic anterior motion (SAM) of the mitral valve caused by the interplay between increased left ventricular (LV) wall thickness and an abnormal mitral valve anatomy and geometry. Three-dimensional (3D) echocardiographic imaging of the mitral valve has revolutionized the practice of cardiology, paving the way for new methods to see and treat valvular heart disease. Here we present the novel and incremental value of 3D transesophageal echocardiography (TEE) of SAM visualization. This review first provides step-by-step instructions on acquiring and optimizing 3D TEE imaging of SAM. It then describes the unique and novel findings using standard 3D TEE rendering as well as dynamic mitral valve modeling of SAM from 3D data sets, which can provide a more detailed visualization of SAM features. The findings include double-orifice LVOT caused by the residual leaflet, the dolphin smile phenomenon, and delineation of SAM width. Finally, the review discusses the essential role of 3D TEE imaging for preprocedural assessment and intraprocedural guidance of surgical and novel percutaneous treatments of SAM.

Introduction/UNASSIGNED:Previous studies have suggested that women with chroniclimb-threatening ischemia (CLTI) may have worse outcomes than men. The aim of this study was to determine whether there are sex-related differences in outcomes of patients with CLTI undergoing endovascular treatment with current endovascular technologies. Patients and Methods/UNASSIGNED:Data were derived from the LIBERTY 360 study (NCT01855412). Hazard ratios and the respective 95% confidence intervals were synthesized to examine the association between sex and all-cause mortality, target vessel revascularization (TVR), major amputation, major adverse event (MAE) and major amputation/death up to 3 years of follow-up. Results/UNASSIGNED:A total of 689 patients with CLTI (female: N=252 vs male: N=437) treated with any FDA approved or cleared device were included. The mean lesion length was 126.9±117.3mm and 127.4±113.3mm for the female and male patients, respectively. Although a slightly higher incidence of in-hospital mortality was observed in the female group (1.2% vs 0.0%, p=0.049), there was no difference in female vs male survival rates during follow-up. However, the risk of major amputation at 18 months was higher for the male group (male vs female: HR: 2.36; 95% CI: 1.09-5.12; p=0.030). No difference between the two groups was detected in terms of TVR or MAE during follow-up. Discussion/UNASSIGNED:Data regarding sex-related disparity in outcomes after endovascular therapy of patients with CLTI are conflicting. Gender-related characteristics rather than biological sex characteristics might be the cause of these conflicting findings. Further studies are needed to evaluate the role of sex in revascularization outcomes among this high-risk population.

Glucose 6-phosphate dehydrogenase (G6PD) deficiency facilitates human coronavirus infection due to glutathione depletion. G6PD deficiency may especially predispose to hemolysis upon coronavirus disease-2019 (COVID-19) infection when employing pro-oxidant therapy. However, glutathione depletion is reversible by N-acetylcysteine (NAC) administration. We describe a severe case of COVID-19 infection in a G6PD-deficient patient treated with hydroxychloroquine who benefited from intravenous (IV) NAC beyond reversal of hemolysis. NAC blocked hemolysis and elevation of liver enzymes, C-reactive protein (CRP), and ferritin and allowed removal from respirator and veno-venous extracorporeal membrane oxygenator and full recovery of the G6PD-deficient patient. NAC was also administered to 9 additional respirator-dependent COVID-19-infected patients without G6PD deficiency. NAC elicited clinical improvement and markedly reduced CRP in all patients and ferritin in 9/10 patients. NAC mechanism of action may involve the blockade of viral infection and the ensuing cytokine storm that warrant follow-up confirmatory studies in the setting controlled clinical trials.

Background Transfemoral (TF) Transcatheter Aortic Valve Replacement (TAVR) has been shown to be at least equivalent to surgery. Nevertheless, many patients do not qualify for TF approach due to severe ilio-femoral (I-F) occlusive disease. The use of an atherectomy device in order to facilitate TF-TAVR has only been reported in case reports. We describe our experience using orbital atherectomy in preparation for TF-TAVR. Methods We searched our prospective database for the last 1000 TAVR procedures. Patient demographics, procedural characteristics, CT characteristics and short-term outcomes were recorded. CT scans were reviewed to assess access. Hostile access was defined as luminal size less than 5 mm, or less than 5.5mm and the presence of more than 270degree calcification. The primary end-point was the ability to successfully deliver a transcatheter valve via the intended, pre-treated access site. Secondary end-points were procedural vascular complications including mortality, stroke, bleeding requiring transfusion, and urgent vascular repair at 30 days. Results From April 2016 to July 2019, 1000 TAVR procedures were performed. Six subjects (0.6%) required alternative access; 68 patients (6.8%) were labeled as having a hostile I-F anatomy that required vessel preparation prior to TAVR. 48 (70.6%) had angioplasty only and 20 (29.4%) required atherectomy and angioplasty. Atherectomy was performed in a range of 5-21 days prior to TAVR; transradial approach was used in 90% of the time. Out of 20 patients treated with atherectomy successful TF delivery of the valve was achieved in 19 (95%). The mean vessel reference diameter in atherectomy group was 4.0+/-0.9mm. All had near-circumferential calcification. There was no in-hospital mortality or stroke. There were no perforations. One subject required placement of a self-expandable stent due to severe dissection. None of the end-points occurred between hospital discharge and 30-day follow-up. Conclusion Orbital atherectomy used for vessel preparation is a safe and very effective technique to facilitate TF-TAVR in patients with hostile peripheral anatomy.
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Background Mitral valve (MV) repair using the MitraClip system is indicated for patients with severe mitral regurgitation (MR) and high surgical risk. However, patients with small MV area are at risk of post procedural mitral stenosis (MS) and have typically been excluded from this therapy. We evaluated MitraClip feasibility in patients with small MV area. Methods Consecutive patients with severe MR were identified. MV area was measured using 3D planimetry. Small MV area was defined as < 4 cm². Procedural success defined as reduction to >= 2+ MR in absence of surgery, or mortality. Primary endpoint was clinically significant MS defined as residual MV gradient >= 5 mmHg and NYHA class III or IV symptoms. NYHA class at 30 days was evaluated. Results 295 patients were treated from Mar 2016 to Jul 2019. Procedural success was seen in 281 of 295 patients (95%). 63 patients (21%) had a small MV area [Median 3.5 cm², range 2.0-3.9]. Mean age (85 +/- 7), female (65%). At baseline NYHA class was: II: 11, III: 39, and IV: 13 patients. Median post procedure MV gradient was 4 mmHg (range 2-7) at a median heart rate of 70. 13/63 patients had MV gradient >= 5 mmHg, of those only two patients had no improvement in NYHA class despite a reduction in MR. 30-day NYHA class I, II, III, and IV symptoms were seen in 30, 24, 8, and 1 patients (P<0.01 for trend). (Figure) Conclusion MV repair using MitraClip is feasible for patients with small MV area. Post procedural clinically significant MS was rare. Studies with long term outcomes are warranted. [Figure presented]
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