Faculty Bibliography

•The risk of thromboembolic events in COVID-19 is substantial•Pulmonary embolism should be considered in cases of clinical deterioration•Management of clot in transit is controversial.

Clinical spectrum of hypertrophic cardiomyopathy (HC) has been expanded to include patients with mild or no thickening of the left ventricle (LV), who nevertheless have outflow tract obstruction at rest or after exercise, due to systolic anterior motion (SAM) and ventricular septal contact, with mitral valve elongation and papillary muscles anomalies. Apical ballooning mimicking a takotsubo syndrome (TS) wall motion pattern can occur in HC with mild septal thickening when latent obstruction becomes unrelenting. To define the prevalence of anatomic abnormalities characteristic of HC in patients diagnosed with TS, we analyzed echocardiograms of 44 unselected TS patients, age 67±12 years, 95% women including studies performed before the event (n = 11, median 515 days) and after recovery of left ventricular function (n = 33, median 92 days, interquartile range = 29 to 327) and compared the findings to 60 age and sexed matched controls. Analysis of echocardiograms was blinded to event timing, and patient vs. control status. During the ballooning event, 13 patients (30%) had SAM including 9 with LV outflow obstruction, peak gradients 71±40 mmHg, as well as: ventricular septal thickening (16 ± 4 mm), elongated anterior leaflets (30 ± 3mm), and increased mitral coaptation to posterior wall distance (17 ± 5 mm), consistent with diagnosis of the HC phenotype. Compared to 31 TS patients without SAM, study patients with SAM had longer anterior leaflets (30 ± 3 vs 26 ± 4 mm, p = 0.006), thicker septum (16 ± 4 vs 12 ± 3 mm), increased coaptation to posterior wall distance (17 ± 5 vs 14 ± 4 mm, p < 0.04) and reduced distance from coaptation to septum (19 ± 5 vs 27 ± 5, p < 0.001). In the 13 patients with SAM, morphologic characteristics of HC persisted after normalization of LV function. In conclusion, a subset of patients experiencing TS events demonstrates a constellation of morphologic abnormalities characteristic of HC that persist after recovery of LV wall motion. These findings suggest that dynamic outflow obstruction may cause apical ballooning in susceptible patients.

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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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 Recently the clinical spectrum of hypertrophic cardiomyopathy (HCM) has been expanded to include patients with mild or no thickening of the left ventricle (LV) yet who have outflow tract obstruction at rest or after exercise, principally due to characteristic HCM anterior mitral leaflet (AML) elongation and papillary muscle anomalies. Apical ballooning mimicking a takotsubo syndrome (TTS) wall motion pattern can occur in mild-septal-thickening HCM when latent obstruction becomes unrelenting. The objective of this study is to define the prevalence of anatomic abnormalities characteristic of HCM in an unselected population of patients diagnosed clinically with TTS. Methods We analyzed echocardiograms of 44 admitted TTS patients including studies performed during admission, before the event (n=11, median 515 days before) and after recovery of left ventricular function (n=33, median 92 days, IQR=29-327) and compared them to 60 controls, age-matched normal women. Analysis of 148 echocardiograms was blinded to timing, and patient vs. control status. Results Age was 67+/-12 years, 42 female (95%). During the ballooning event, 13 (30%) had SAM and 9 patients (20%) had LV outflow tract obstruction (LVOTO), gradients 71+/-40 mmHg. Compared to TTS patients without SAM, those with SAM had longer AML (30 vs. 26mm), and thicker septum (16 vs. 12 mm) and less distance from septum to coaptation (19 vs. 27mm), all p <=0.006. Eleven of the SAM patients had >=2 anatomic abnormalities predisposing to obstruction (defined as > 2 SD above normal), and/or an anomalous papillary muscle/chordae. In the 44 TTS patients each parameter differed from controls before, during and after the TTS event. Eight (18%) had abnormal right ventricular wall motion, none of whom were obstructed. Conclusion Thirty percent of unselected TTS patients have SAM and 20% have significant LVOT gradients. This subset had AML abnormalities and septal thickening typical of obstructive HCM and known to predispose to LVOT obstruction. They are phenotypically identical to patients with documented HCM with mild septal thickening and LVOT obstruction, who have experienced episodes of ballooning.

The 2019 American College of Cardiology Scientific Sessions displayed innovation in many areas for the evaluation and management of cardiovascular disease from preventive evaluation and care to advanced interventions. Imaging played a central role in these developments with a highlight of the conference being the imaging research presented. This review will summarize key imaging studies which were presented at this scientific meeting which will lead to innovation in the evaluation and management of cardiovascular disease. Experts in nuclear imaging (DW/MA), echocardiography (MS), cardiac magnetic resonance (SL), and cardiac computed tomography (RB) selected abstracts which they found to be of particular interest to the multimodality imaging audience and were integrated into this review (LP).