Thibault Caspar

Von Willebrand Factor Multimers during Transcatheter Aortic-Valve Replacement

BACKGROUND Postprocedural aortic regurgitation occurs in 10 to 20% of patients undergoing transcatheter aortic-valve replacement (TAVR) for aortic stenosis. We hypothesized that assessment of defects in high-molecular-weight (HMW) multimers of von Willebrand factor or point-of-care assessment of hemostasis could be used to monitor aortic regurgitation during TAVR. METHODS We enrolled 183 patients undergoing TAVR. Patients with aortic regurgitation after the initial implantation, as identified by means of transesophageal echocardiography, underwent additional balloon dilation to correct aortic regurgitation. HMW multimers and the closure time with adenosine diphosphate (CT-ADP), a point-of-care measure of hemostasis, were assessed at baseline and 5 minutes after each step of the procedure. Mortality was evaluated at 1 year. A second cohort (201 patients) was studied to validate the use of CT-ADP in order to identify patients with aortic regurgitation. RESULTS After the initial implantation, HMW multimers normalized in patients without aortic regurgitation (137 patients). Among the 46 patients with aortic regurgitation, normalization occurred in 20 patients in whom additional balloon dilation was successful but did not occur in the 26 patients with persistent aortic regurgitation. A similar sequence of changes was observed with CT-ADP. A CT-ADP value of more than 180 seconds had sensitivity, specificity, and negative predictive value of 92.3%, 92.4%, and 98.6%, respectively, for aortic regurgitation, with similar results in the validation cohort. Multivariable analyses showed that the values for HMW multimers and CT-ADP at the end of TAVR were each associated with mortality at 1 year. CONCLUSIONS The presence of HMW-multimer defects and a high value for a point-of-care hemostatic test, the CT-ADP, were each predictive of the presence of aortic regurgitation after TAVR and were associated with higher mortality 1 year after the procedure. (Funded by Lille 2 University and others; ClinicalTrials.gov number, NCT02628509.).

Effects of Transcutaneous Aortic Valve Implantation on Aortic Valve Disease-Related Hemostatic Disorders Involving von Willebrand Factor

BACKGROUND Aortic valve stenosis (AVS) can be complicated by bleeding associated with acquired type 2A von Willebrand syndrome. The association of AVS and gastrointestinal bleeding from angiodysplasia is defined as Heyde syndrome. We sought to evaluate the effect of transcutaneous aortic valve implantation (TAVI) on hemostasis disorders and to assess its effectiveness to treat Heyde syndrome. METHODS We prospectively enrolled 49 consecutive patients with severe AVS addressed for TAVI at our institution. Biological hemostasis parameters involving von Willebrand factor (vWF) were assessed at baseline and 1 week after the procedure. RESULTS At baseline, a significant link between vWF abnormalities and the severity of AVS was evidenced: mean aortic transvalvular gradient was negatively correlated with the levels of vWF antigen (vWF:Ag) (r = -0.29; P < 0.05), vWF ristocetin cofactor activity (r = -0.402; P = 0.006), and vWF collagen-binding activity (vWF:CB; r = -0.441; P = 0.005). One week after the procedure, a significant increase of vWF:Ag, vWF ristocetin cofactor activity, and vWF:CB was evidenced in the whole cohort (respectively, 3.32 vs. 2.29 IU/mL, P < 0.001; 2.98 vs. 1.86 IU/mL, P < 0.001; and 3.16 vs. 2.16 IU/mL, P < 0.001). Patients with pre-TAVI vWF abnormalities consistent with a type 2A vWF syndrome (ratio vWF:CB/vWF:Ag < 0.7) preferentially improved their vWF function with respect to patients with a normal ratio (relative increase of vWF:CB of 63.8% vs. 3.5%). CONCLUSIONS Hemostasis parameters involving vWF are improved after TAVI, especially in patients with pre-existing abnormalities consistent with acquired type 2A von Willebrand syndrome.

Longitudinal 2D strain can help diagnose coronary artery disease in patients with suspected non-ST-elevation acute coronary syndrome but apparent normal global and segmental systolic function

BACKGROUND The clinical work-up of patients presenting with chest pain is a diagnostic challenge. We investigated the diagnostic performance of global (GLS) and territorial (TLS) longitudinal strain to predict coronary artery disease (CAD) in patients presenting with suspected non-ST-segment elevation acute coronary syndrome (NSTE-ACS) but apparent normal global and regional systolic function. METHODS 150 consecutive suspected NSTE-ACS patients were initially screened for inclusion ; 58 patients with normal LVEF (≥55%) and WMSI (=1) were prospectively enrolled. Speckle-tracking echocardiography was performed on admission and all the patients underwent coronary angiography. CAD was defined as the presence of stenosis of >50%. RESULTS CAD was present in 33 patients (57%). LVEF was 60.7±4.6% in group 1 (CAD) and 61.1±5.0% in group 2 (no CAD). Global longitudinal strain (GLS) was altered in group 1 (-16.7±3.4%) as compared to group 2 (-22.4±2.9%, p<0.001). ROC curve analysis showed a high diagnostic value of GLS for the prediction of CAD (AUC=0.92 [0.84-1.00], p=0.0001). TLS was able to discriminate between coronary stenosis in the LAD, LCX or RCA. CONCLUSIONS Longitudinal 2D strain has a good diagnostic value and can efficiently localize the culprit lesion in patients presenting with NSTE-ACS but apparent normal global and regional systolic function.

Late Detection of Left Ventricular Dysfunction Using Two-Dimensional and Three-Dimensional Speckle-Tracking Echocardiography in Patients with History of Nonsevere Acute Myocarditis

Background: Acute myocarditis (AM) often involves the left ventricular (LV) subepicardium that might be displayed by cardiac magnetic resonance even late after the acute phase. In the absence of global or regional LV dysfunction, conventional transthoracic echocardiography (TTE) does not accurately identify tissue sequelae of AM. We sought to evaluate the diagnostic value of two‐dimensional (2D) and three‐dimensional (3D) speckle‐tracking echocardiography to identify patients with a history of AM with preserved LV ejection fraction (LVEF). Methods: Fifty patients (group 1: age, 31.4 ± 10.5 years; 76% males) with a history of cardiac magnetic resonance–confirmed diagnosis of AM (according to the Lake Louise criteria) were retrospectively identified and then (21.7 ± 23.4 months later) evaluated by complete echocardiography including 2D and 3D speckle‐tracking analysis, as well as 50 age‐ and gender‐matched healthy controls (group 2: age, 31.2 ± 9.5 years: 76% males). Patients with a history of severe clinical presentation of AM (sudden death, ventricular arrhythmia, heart failure, alteration of LVEF) were excluded. Results: At diagnosis, peak troponin and C‐reactive protein were 11.97 (interquartile range, 4.52‐25.92) &mgr;g/L and 32.3 (interquartile range, 14.85‐70.45) mg/L, respectively. Mean delay between acute phase and follow‐up study TTE was 21.7 ± 23.4 months. LVEF was not statistically different between groups (62.1% vs 63.5%, P = .099). Two‐dimensional global longitudinal strain (GLS) was lower in magnitude in group 1 (−17.8% vs −22.1%, P < .0001) as were 2D layer‐specific subepicardial GLS (−15.4% vs −19.7%, P < .0001) and subendocardial GLS (−20.71% vs −25.08%, P < .0001). Three‐dimensional global longitudinal, circumferential, area, and radial strains were lower in magnitude in group 1 (−11.80% vs −14.98%, P < .0001; −12.57% vs −15.12%, P < .0001; −22.28% vs −25.87%, P < .0001; 31.47% vs 38.06%, P < .0001, respectively). Receiver operating characteristic curve analysis showed that subepicardial GLS displayed a better diagnostic performance to detect sequelae of AM as compared with GLS (area under the curve = 0.97 vs 0.93, P = .045). Conclusions: In patients with a history of AM, a subtle LV dysfunction can be detected by 2D and 3D speckle‐tracking echocardiography, even though LVEF is conserved, adding incremental information over conventional TTE. HighlightsIn patients with a history of AM, a subtle myocardial dysfunction can be detected even late after the episode.Both LV and right ventricular strain parameters are altered compared with healthy controls.Layer‐specific 2DSTE is useful to detect subepicardial alteration of LV longitudinal function.These tools represent a potential novel approach for noninvasive multimodality evaluation of AM patients.

CT-ADP Point-of-Care Assay Predicts 30-Day Paravalvular Aortic Regurgitation and Bleeding Events following Transcatheter Aortic Valve Replacement

BACKGROUND Paravalvular aortic regurgitation (PVAR) remains a frequent postprocedural concern following transcatheter aortic valve replacement (TAVR). Persistence of flow turbulence results in the cleavage of high-molecular-weight von Willebrand multimers, primary haemostasis dysfunction and may favour bleedings. Recent data have emphasized the value of a point-of-care measure of von Willebrand factor-dependent platelet function (closure time [CT] adenosine diphosphate [ADP]) in the monitoring of immediate PVAR. This study examined whether CT-ADP could detect PVAR at 30 days and bleeding complications following TAVR. METHODS CT-ADP was assessed at baseline and the day after the procedure. At 30 days, significant PVAR was defined as a circumferential extent of regurgitation more than 10% by transthoracic echocardiography. Events at follow-up were assessed according to the Valve Academic Research Consortium-2 consensus classification. RESULTS Significant PVAR was diagnosed in 44 out of 219 patients (20.1%). Important reduction of CT-ADP could be found in patients without PVAR, contrasting with the lack of CT-ADP improvement in significant PVAR patients. By multivariate analysis, CT-ADP > 180 seconds (hazard ratio [HR]: 5.1, 95% confidence interval [CI]: 2.5-10.6; p < 0.001) and a self-expandable valve were the sole independent predictors of 30-day PVAR. At follow-up, postprocedural CT-ADP >180 seconds was identified as an independent predictor of major/life-threatening bleeding (HR: 1.7, 95% CI [1.0-3.1]; p = 0.049). Major/life-threatening bleedings were at their highest levels in patients with postprocedural CT-ADP > 180 seconds (35.2 vs. 18.8%; p = 0.013). CONCLUSION Postprocedural CT-ADP > 180 seconds is an independent predictor of significant PVAR 30 days after TAVR and may independently contribute to major/life-threatening bleedings.

Characterization of an intra-cardiac melanoma metastasis by magnetic resonance T1 and T2 mapping

This case demonstrates how the integration of new cardiac imaging techniques can contribute to the exploration of a cardiac mass, and ultimately help the etiological diagnosis. Recent years have witnessed the advent of the use of new CMR T1 and T2 mapping sequences [1]: access to a true absolute quantification of relaxation times rather than a simple weighting of the image contrast is a material change in MRI. If T1 and T2 mapping sequences have been already extensively described in the setting of cardiomyopathies, only seldom case reports have focused on T1 or T2 mapping in cardiac masses [2]. To our knowledge, this is the first report of an intracardiac melanoma being evaluated by CMR Tx mapping. These sequences allow a significant progress in the approach of tissue characterization, providing complementary information to that of other imaging modalities and thus can be useful for the evaluation of cardiac tumors and masses. A 64 year-old male patient with a history of melanoma was referred to our department for cardiac magnetic resonance (CMR) evaluation of an intra-cardiac mass. The echocardiography showed an ovoid tumoral mass embedded in the right atrial floor, just behind the tricuspid annulus, suspected to be a cardiac location of melanoma metastasis. CMR 1.5T T1 and T2 mapping sequences revealed low native T1 value inside the mass (736 ms) (Fig. 1, panel A) in comparison to myocardium (normal range 1030 ± 34 ms) consistent with a melanin content whose paramagnetic effect is related to the presence of free radicals and non-apparied electrons, and slightly elevated T2 (58 ms, normal range 50 ± 2 ms) (Fig. 1, panel B). After gadolinium injection, post-contrast T1 mapping sequence showed a 59 % T1 drop in the tumor (Fig. 1, panel C) and late-enhancement was clearly identified with PSIR sequence disclosing heterogeneous uptake inside the mass (Fig. 1, panel D). The tumor was surgically removed and histopathology confirmed the diagnosis of melanoma metastasis.

Idiopathic myocardial calcification: Insights from multimodality imaging

Article history: Received 3 June 2016 Accepted 9 July 2016 Available online 11 July 2016 T1 and T2 mapping in mass revealed low T1 (370 ms vs 1050 ms in the remote LV lateral myocardium) and T2 values (43 ms vs 50 ms in the remote LV lateral myocardium) (Fig. 1C, D, E). Contrast technique showed no late gadolinium enhancement (LGE) in themass itself except at its periphery (Fig. 1F). Therewas apical trans-mural LGE, but no LGE of ischemic or non-ischemic distribution in the over-all IVS wall (Fig. 1F).

Left Ventricular Function Evaluation on a 3T MR Scanner with Parallel RF Transmission Technique: Prospective Comparison of Cine Sequences Acquired before and after Gadolinium Injection.

Objectives To compare cine MR b-TFE sequences acquired before and after gadolinium injection, on a 3T scanner with a parallel RF transmission technique in order to potentially improve scanning time efficiency when evaluating LV function. Methods 25 consecutive patients scheduled for a cardiac MRI were prospectively included and had their b-TFE cine sequences acquired before and right after gadobutrol injection. Images were assessed qualitatively (overall image quality, LV edge sharpness, artifacts and LV wall motion) and quantitatively with measurement of LVEF, LV mass, and telediastolic volume and contrast-to-noise ratio (CNR) between the myocardium and the cardiac chamber. Statistical analysis was conducted using a Bayesian paradigm. Results No difference was found before or after injection for the LVEF, LV mass and telediastolic volume evaluations. Overall image quality and CNR were significantly lower after injection (estimated coefficient cine after > cine before gadolinium: -1.75 CI = [-3.78;-0.0305], prob(coef>0) = 0% and -0.23 CI = [-0.49;0.04], prob(coef>0) = 4%) respectively), but this decrease did not affect the visual assessment of LV wall motion (cine after > cine before gadolinium: -1.46 CI = [-4.72;1.13], prob(coef>0) = 15%). Conclusions In 3T cardiac MRI acquired with parallel RF transmission technique, qualitative and quantitative assessment of LV function can reliably be performed with cine sequences acquired after gadolinium injection, despite a significant decrease in the CNR and the overall image quality.

0353: Impact of TAVI on primary hemostasis, von Willebrand factor and Heyde’s syndrome: a prospective monocenter study

Background Aortic valve stenosis (AVS) can be complicated by bleeding associated with acquired type 2A von Willebrand syndrome. The association of AVS and gastrointestinal bleeding from angiodysplasia is defined as Heyde’s syndrome. We sought to evaluate the impact of TAVI on primary hemostasis disorders and to assess its effectiveness to treat Heyde’s syndrome. Methods We prospectively enrolled 49 consecutive patients with severe AVS referred to our institution for TAVI. Biological primary hemostasis parameters were assessed at baseline and one week after the procedure. Results At baseline, a significant link between vWF abnormalities and the severity of AVS was evidenced: mean aortic transvalvular gradient was negatively correlated with the levels of vWF antigen (vWF: Ag) (r=–0.29, p Conclusion Primary hemostasis parameters involving vWF are improved after TAVI, especially in patients with preexisting abnormalities consistent with acquired type 2A von Willebrand syndrome. Moreover, our observations, although limited to a small single-center study, suggest that Heyde’s syndrome can be cured by TAVI.

TCT-765 Impact Of TAVI On Primary Hemostasis, Von Willebrand Factor And Heyde’s Syndrome: A Prospective Monocenter Study

Aortic valve stenosis (AVS) can be complicated by bleeding associated with acquired type 2A von Willebrand syndrome. The association of AVS and gastrointestinal bleeding from angiodysplasia is defined as Heydes syndrome. We sought to evaluate the impact of TAVI on primary hemostasis disorders and