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.

The COVID-19 pandemic has presented countless new challenges for healthcare providers including the challenge of differentiating COVID-19 infection from other diseases. COVID-19 infection and acute endocarditis may present similarly, both with shortness of breath and vital sign abnormalities, yet they require very different treatments. Here, we present two cases in which life-threatening acute endocarditis was initially misdiagnosed as COVID-19 infection during the height of the pandemic in New York City. The first was a case of Klebsiella pneumoniae mitral valve endocarditis leading to papillary muscle rupture and severe mitral regurgitation, and the second a case of Streptococcus mitis aortic valve endocarditis with heart failure due to severe aortic regurgitation. These cases highlight the importance of careful clinical reasoning and demonstrate how cognitive errors may impact clinical reasoning. They also underscore the limitations of real-time reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2 testing and illustrate the ways in which difficulty interpreting results may also influence clinical reasoning. Accurate diagnosis of acute endocarditis is critical given that surgical intervention can be lifesaving in unstable patients.

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.

Tricuspid regurgitation (TR) is an uncommon and underdiagnosed complication of blunt chest trauma. Typical mechanisms include torn chordae, papillary muscle rupture, and radial leaflet tear. We describe an unusual case of traumatic TR due to circumferential avulsion of the anterior tricuspid leaflet from the tricuspid annulus and the crucial role of multimodality imaging in its diagnosis and treatment. (Level of Difficulty: Intermediate.).

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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Background Software to fuse transesophageal echocardiography (TEE) images onto live fluoroscopy (FL) allows for fluoroscopic visualization of TEE-derived anatomic landmarks. We compared transcatheter Paravalvular Leak (PVL) Closure using TEE / Truefusion versus TEE / FL guidance only. Methods This prospective pilot study evaluated the safety and feasibility of the TrueFusion software in subjects scheduled for paravalvular leak (PVL) closure. Immediately prior to the procedure, TEE and FL systems were co-registered and anatomical markers for the source of PVL were generated. Procedural outcomes recorded were the reduction in regurgitant grade, procedural time, FL time, and radiation exposure. They were compared between patients who underwent PVL closure with and without TrueFusion. Results The cohort (n=27), Male (60%), age 72 +/- 15 years. 15 subjects underwent TrueFusion-guided PLV closure (10 mitral and 5 aortic). Eleven subjects had non-TrueFusion PVL closure (5 mitral and 2 aortic). TrueFusion-guided PVL closures demonstrated significantly greater achievement of at least one grade reduction in PVL severity (p=0.02). Use of TrueFusion group also showed a non-statistically significant trend toward lower median FL time, mean dose area product, and mean procedural time when compared to PVL closures without TrueFusion guidance (Figure). Conclusion The co-registration of TEE and fluoroscopy images using the TrueFusion software potentially improves efficiency outcomes. [Figure presented]
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Background Transesophageal echocardiography (TEE) is the gold standard for determining mitral regurgitant (MR) leaflet morphology and suitability for edge-to-edge (E2E) repair. Computed tomography (CT) has become essential for evaluation for transcatheter mitral valve replacement (TMVR) and has the temporal and spatial resolution to show leaflet abnormalities with great clarity (figure) but the correlation of findings with TEE has not been well studied. Methods A consecutive series of patients attending clinic for moderate-severe or greater mitral regurgitation underwent CT and TEE. Data was analyzed for leaflet morphology with blinded independent analyses by CT and TEE expert readers. Results A study flow diagram is shown (figure). Mean age was 79.6 (SD 10.9) and mean STS score (repair) was 4.8% (SD3.7). Analyses were independently performed (figure). There was a strong correlation between mitral valve orifice area (MVOA) by CT and TEE (r=0.86, p<0.001), however MVOA was on average 0.45 cm² larger (p=0.003) on CT (5.24cm², SD 1.84) than TEE (4.79cm², SD 1.91). For those cases where CT could make an interpretation on suitability for E2E repair there was 100% concordance between CT and TEE (figure). Conclusion In this preliminary retrospective analysis, a comparison of CT and TEE suggested that CT may be a useful non-invasive modality for the assessment of mitral leaflet morphology and suitability for E2E repair. A prospective comparison is ongoing and will be completed at the time of presentation. [Figure presented]
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Background Patients with chronic kidney disease (CKD) have poor short-term outcomes after transcatheter aortic valve replacement (TAVR). Methods Retrospective review identified 575 consecutive patients not on hemodialysis (HD) who underwent TAVR at a single center between September 2014 and January 2017. Patients were stratified by pre-procedural glomerular filtration rate (GFR) [>60 (n=297), 30-60 (n=242), and <30 (n=36)]. Outcomes were defined by VARC-2 criteria. Median follow-up was 811 days. Results Transfemoral artery access (TFA), used in 98.8%, and VARC-2 defined procedural success, achieved in 81.4%, did not differ between groups. However, rates of peri-procedural stroke (0.7%, 2.1%, 11.1%; p<0.001) and acute kidney injury (0%, 1.7%, 8.3%; p<0.001) were higher with lower GFR. When compared to GFR >60, risk of all-cause mortality was higher with GFR 30-60 (Hazard ratio (HR) 1.61 [1.00-2.59]) and GFR <30 (HR 2.41 [1.06-5.49]). After adjustment for differences in baseline and procedural characteristics, all-cause mortality remained higher with GFR <60 (adjusted HR 1.67 [1.03-2.70]) compared with GFR >60. Rate of long-term all-cause mortality was higher with lower GFR (10.1%, 16.5%, 19.4%). Kaplan-Meier mortality estimates are shown. Conclusion Few patients with a pre-procedural GFR <30 but not HD undergo TAVR. Despite high use of TFA and no difference in procedural success rate, long-term all-cause mortality after TAVR is higher in patients with pre-procedural CKD. [Figure presented]
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Background Computed tomography (CT) has become the standard of care for assessment for the suitability for transcatheter mitral valve replacement (TMVR); however, variation in mitral annular measurements across the cardiac cycle has thus far been poorly studied. Because of this, currently TMVR assessment is cumbersome and involves the assessment of multiple phases. We sought to further understand variation in mitral annular dimensions with the cardiac cycle and assess its potential implications for Methods A total of 118 patients presented to the heart valve clinic and underwent CT for possible TMVR assessment and were consecutively studied with multiphase CT. The mitral annulus was measured in 10 phases using 3mensio mitral planning software and several parameters collected including perimeter, area, anterior-posterior (AP) dimension and commissure-commissure (CC) dimension. Results Of the 118 patients screened, 83.9% had predominant MR, 10.2% mixed MS/MR and 5.9% predominant MS. Changes in perimeter, Area, AP and CC dimensions are shown (figure). Comparison of largest and smallest mean measurements for each phase for perimeter, Area, AP and CC dimensions showed a 2.02%, 4.36%, 8.09% and 2.86% variation respectively. Conclusion In contrast to the dynamism of the aortic annulus and neo-LVOT, the mitral annulus does not vary significantly. This may allow limitation of radiation restricting CT acquisitions to mid-systole where the neo-LVOT is smallest. [Figure presented]
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