Patrick Garceau

The Amplatzer™ Cardiac Plug 2 for left atrial appendage occlusion: novel features and first-in-man experience.

Percutaneous left atrial appendage (LAA) closure is becoming a frequently performed procedure for patients with atrial fibrillation and high haemorrhagic risk. The Amplatzer™ Cardiac Plug (ACP) is one of the most commonly used devices for this purpose. Despite high success rate and low procedure risk associated with the ACP, a second generation of the device is now available. The new ACP has been designed to facilitate the implantation process, improve sealing performance and further reduce the risk of complications. The present report focuses on the novel features of the second generation of the Amplatzer™ Cardiac Plug (ACP 2 or Amulet™) and describes the first-in-man experience.

Comparison of two different speckle tracking software systems: does the method matter?

Background: Echocardiographic speckle tracking strain has gained clinical importance. However, the comparability of measurements between different software systems is not well defined. Methods: In 47 healthy subjects left ventricular (LV) two‐dimensional (2D) peak strain and time to peak strain (TTP) generated by EchoPAC (2DS) and velocity vector imaging (VVI) were compared. For each type of strain (longitudinal [LS], circumferential [CS], and radial strain [RS]) we compared global, anatomical level and segmental values. Results: When comparing 2DS to VVI, Pearson correlation coefficients (r) of global LS, CS, and RS were 0.68, 0.44, and 0.59, respectively (all P < 0.05). Correlation of global TTP was higher: 0.81(LS), 0.80 (CS), and 0.68 (RS), all P < 0.01. Segmental peak strain differed significantly between 2DS and VVI in 8/18 (LS), 17/18 (CS), and 15/18 (RS) LV segments (P < 0.05). However, segmental TTP significantly differed only in 5/18 (LS), 7/18 (CS), and 4/18 (RS) of LV segments. Similar strain gradients were found for both systems: apical strain was higher than basal and midventricular strain in LS and CS, with a reversed pattern for RS (P < 0.05). Conclusion: TTP strain as well as strain gradients were comparable between VVI and 2DS, but most peak strain values were not. The software‐dependency of peak strain values must be considered in clinical application. Further studies comparing the diagnostic and prognostic accuracy of strain values generated by different software systems are mandatory. (Echocardiography 2011;28:539‐547)

Left atrial appendage occlusion: Initial experience with the Amplatzer™ Amulet™☆

BACKGROUND The Amplatzer™ Amulet™ (Amulet) is the evolution of the Amplatzer™ Cardiac Plug, a dedicated device for percutaneous left atrial appendage (LAA) occlusion. The new device has been designed to facilitate the implantation process, improve the sealing performance and further reduce the risk of complications. The objective of the study was to describe the initial experience with the Amplatzer Amulet for percutaneous LAA occlusion. METHODS This was a prospective single-center study of patients undergoing percutaneous LAA occlusion. The indication for LAA closure was a formal contraindication for oral anticoagulation or previous history of stroke due to INR lability. All procedures were done under general anesthesia and transesophageal echocardiography (TEE) guidance. Transthoracic echocardiography was performed 24h after the procedure in order to rule out procedural complications before discharge. Further follow-up was done with a clinical visit and TEE at 1-3 months. RESULTS Between July-2012 and June-2013, 25 patients with a mean CHA2DS2-VASC of 4.3 ± 1.7 underwent LAA occlusion with the Amplatzer Amulet. The device was successfully implanted in 24 patients (96%) without any procedural stroke, pericardial effusion or device embolization. None of the patients presented any clinical event at follow-up. Follow-up TEE showed complete LAA sealing in all patients with no residual leaks >3mm and no device embolization. One patient (4.1%) presented a device thrombosis at follow-up without clinical expression. CONCLUSION In this initial series of patients, the Amulet showed a remarkable acute and short-term performance in terms of feasibility and safety as depicted by the high successful implantation rate and the low incidence of complications.

Left Ventricular Strain Patterns in Dilated Cardiomyopathy Predict Response to Cardiac Resynchronization Therapy: Timing Is Not Everything

BACKGROUND Cardiac resynchronization therapy (CRT) is not uniformly helpful in heart failure, and the determination of baseline dyssynchrony does not improve its success rate. The aim of this study was to develop prediction rules for successful CRT on the basis of mechanical strain patterns of left ventricular function rather than just the timing of activation. METHODS Seventy-six patients had CRT devices implanted from 2003 to 2006 and underwent echocardiography before and after device implantation. RESULTS Responders (n = 44), determined by >or=10% improvement in ejection fraction and/or >or=15% decrease in end-systolic volume, and nonresponders (n = 32) had similar baseline clinical and echocardiographic characteristics, which improved only in responders. Resynchronization was achieved in both groups. Two-dimensional speckle-tracking longitudinal strain patterns were correlated with response. The absence of passive compliant segments (>or=+5% holosystolic stretching) was 98% sensitive, 88% specific, and had positive and negative predicting values of 91% and 97%, respectively, for response. Adding the presence of lateral delay to this model increased sensitivity to 100% and specificity to 94%. CONCLUSION Left ventricular strain patterns are highly predictive of response to CRT.

Tiara: a novel catheter-based mitral valve bioprosthesis: initial experiments and short-term pre-clinical results.

To the Editor: Novel percutaneous transcatheter technologies are emerging as alternatives to surgery for high-risk patients ([1][1]). Transcatheter mitral valve (MV) implantation has the potential to become the preferred intervention to treat severe mitral regurgitation in these patients, because

Transapical Mitral Implantation of the Tiara Bioprosthesis: Pre-Clinical Results

OBJECTIVES This study sought to describe the pre-clinical evaluation of transapical mitral implantation of the Tiara (Neovasc Inc, Vancouver, British Columbia, Canada) valve in preparation for first-in-man implantation. BACKGROUND The Tiara is a transcatheter self-expanding mitral bioprosthesis, specifically designed for the complex anatomic configuration of the mitral apparatus. METHODS Tiara valves were implanted in a short-term porcine model, in a long-term ovine model, and in human cadavers. RESULTS Short-term and long-term evaluation demonstrated excellent function and alignment of the valves, with no left ventricular outflow tract obstruction, coronary artery obstruction, or transvalvular gradients. Long-term evaluation of 7 sheep demonstrated clinically stable animals. A mild degree of prosthetic valve regurgitation was seen in 2 of the 7 sheep. A mild-to-moderate degree of paravalvular leak, which was attributed to this animal model, was observed in 6 of these animals. Cardioscopy and macroscopic evaluation demonstrated stable and secure positioning of the Tiara valve with no evidence of injury to the ventricular or atrial walls. Pericardial leaflets were free and mobile without calcifications. Implantation of the Tiara valves in human cadaver hearts demonstrated, upon visual inspection, proper anatomic alignment and seating of the valve, both at the atrial and at the ventricular aspects of the native mitral apparatus. CONCLUSIONS In preparation for the first-in-man transcatheter mitral valve implantation, we report the successful pre-clinical evaluation of the Tiara transcatheter self-expanding mitral bioprosthetic valve. In porcine and ovine models without mitral regurgitation, transapical mitral implantation of the Tiara valve is technically feasible and safe, and results in a stable and well-functioning mitral bioprosthesis.

Evaluation of Left Ventricular Relaxation and Filling Pressures in Obstructive Hypertrophic Cardiomyopathy: Comparison between Invasive Hemodynamics and Two-Dimensional Speckle Tracking

Background: Hypertrophic cardiomyopathy (HCM) is usually associated with marked diastolic dysfunction, characterized by impaired myocardial relaxation and increased myocardial stiffness. The noninvasive evaluation of diastolic function in these patients remains a challenge since usual methods have shown a modest correlation with invasive measurements of left ventricular (LV) relaxation and filling pressures. Methods and Results: We retrospectively analyzed 44 patients with obstructive HCM who underwent cardiac catheterization and echocardiography performed within 48 hours. Standard echocardiographic diastolic parameters and systolic and diastolic myocardial mechanics (including longitudinal and circumferential strain [S] and strain rate [Sr]), LV rotation, and early reverse rotation rate (fraction of early apical reverse rotation [FEARR]) were correlated with diastolic hemodynamic indices. Estimated LA pressure by echo and the LV end‐diastolic pressure (LVEDP) or the LV pre‐A pressure did not correlate. Longitudinal strain was low and circumferential strain was abnormally higher than normal. FEARR and negative dp/dt inversely correlated (R =−0.57, P = 0.0001), and early diastolic Sr to systolic Sr ratio (SrE/SrS) correlated with the LVEDP (r = 0.61, P < 0.0001). Furthermore, a SrE to SrS ratio ≥0.79 had a sensitivity of 87% and a specificity of 75% for predicting elevated LVEDP (≥15 mmHg). Average circumferential strain rate during atrial contraction and LV pre‐A pressure (r =−0.62, P < 0.001) inversely correlated. Conclusions: FEARR is decreased in HCM and appears to be a good measure of diastolic dysfunction. Myocardial mechanics can be used to assess LV relaxation and filling pressures in patients with obstructive HCM.

Contractile reserve assessed using dobutamine echocardiography predicts left ventricular reverse remodeling after cardiac resynchronization therapy: prospective validation in patients with left ventricular dyssynchrony.

Background: The presence of viable myocardium may predict response to cardiac resynchronization therapy (CRT). The aim of this study is to evaluate in patients with left ventricular (LV) dyssynchrony whether response to CRT is related to myocardial viability in the region of the pacing lead. Methods: Forty‐nine consecutive patients with advanced heart failure, LV ejection fraction < 35%, QRS duration > 120 ms and intraventricular asynchronism ≥ 50 ms were included. Dobutamine stress echocardiography was performed within the week before CRT implantation. Resting echocardiography was performed 6 months after CRT implantation. Viability in the region of LV pacing lead was defined as the presence of viability in two contiguous segments. Response to CRT was defined by evidence of reverse LV remodeling (≥15% reduction in LV end‐systolic volume). Results: Thirty‐one patients (63%) were identified as responders at follow‐up. The average of viable segments was 5.9 ± 2 in responders and 3.2 ± 3 in nonresponders (P = 0.0003). Viability in the region of the pacing lead had a sensitivity of 94%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 86% for the prediction of response to CRT. Conclusions: In patients with LV dyssynchrony, reverse remodeling after CRT requires viability in the region of the pacing lead. This simple method using echocardiography dobutamine for the evaluation of local viability (i.e., viability in two contiguous segments) may be useful to the clinician in choosing the best LV lead positioning. (Echocardiography 2010;27:668‐676)

Treatment delays in patients undergoing primary percutaneous coronary intervention for ST elevation myocardial infarction at the Quebec Heart and Lung Institute

BACKGROUND Current guidelines for ST elevation myocardial infarction (STEMI) recommend performing primary percutaneous coronary intervention (PCI) within 90 min of hospital arrival. However, recent data suggest that in a real-world setting, median door-to-balloon (DTB) time is closer to 180 min for transfer patients, with less than 5% of patients being treated within 90 min. A retrospective observational study was conducted to assess time to treatment in patients undergoing primary PCI at the Quebec Heart and Lung Institute (QHLI). METHODS Consecutive lytic-eligible patients undergoing primary PCI at the QHLI for STEMI between April 2004 and March 2005 were included in the present analysis. The primary evaluation was DTB time measured from arrival at the first hospital to first balloon inflation. Clinical outcomes were in-hospital death, reinfarction and bleeding. DTB times and hospital outcomes of patients transferred from referring hospitals were compared with those of patients presenting directly to the QHLI. RESULTS During the study period, 203 lytic-eligible patients were treated with primary PCI. Sixty-nine patients presented directly to the QHLI and 134 were transferred from other hospitals. Six transfer patients were excluded because of missing time variables. The median DTB time was 114 min in transfer patients, compared with 87 min in patients presenting directly to the QHLI (P<0.001). DTB time was less than 90 min in 24% of the transfer population compared with 55% of patients presenting directly to the QHLI (P<0.001). In patients referred from hospitals within a radius of 30 km from the QHLI (n=100), median DTB time was 106 min with 30% receiving PCI within 90 min. In these patients, estimated PCI-related delay was 74 min. For patients presenting to hospitals beyond 30 km (n=28), median DTB time was 142 min with 4% receiving reperfusion within 90 min. In these patients, estimated PCI-related delay was 110 min. Median DTB time for patients presenting during off hours at the QHLI was 92 min compared with 79 min for patients presenting during regular business hours (P=0.02). In patients transferred from other hospitals, median DTB time was 118 min during off hours and 108 min during normal business hours (P=0.07). CONCLUSIONS A DTB time of less than 90 min can be achieved in the majority of patients presenting directly to a primary PCI centre. However, for patients presenting to community hospitals, transfer for primary PCI is often associated with delayed revascularization. The present study highlights the need for careful patient selection when deciding between on-site thrombolytic therapy and transfer for primary PCI for STEMI patients presenting to hospitals without PCI facilities.

Initial clinical experience with the GORE septal occluder for the treatment of atrial septal defects and patent foramen ovale.

AIMS To describe the initial experience with the GORE® septal occluder (GSO), a new septal occluder for the treatment of atrial septal defects (ASD) and patent foramen ovale (PFO). METHODS AND RESULTS This was a prospective single-centre review of patients undergoing percutaneous closure for a PFO or ASD with the GSO. A clinical evaluation and follow-up echocardiography were performed at three months with transoesophageal echocardiography (TEE) in case of PFO and transthoracic echocardiography (TTE) in ASDs. Between July 2011 and February 2012, thirty-eight patients underwent PFO (n=29) or ASD (n=9) closure with the GSO using TEE (n=36, 94.7%) or intracardiac echocardiography (n=2, 5.3%) guidance. In PFOs, three-month TEE was available in 24 patients and showed no residual shunt in 18 (75%), bubble shunt in two (8.3%) and bubble shunt after Valsalva in four (16.7%). In ASDs, three-month TTE showed no shunt in eight patients (88.8%) and residual shunt in one patient (11.2%). There was no device embolisation, air embolism, procedure-related stroke or pericardial effusion. No neurological events occurred during the follow-up period. CONCLUSIONS This initial experience with the new GSO device has demonstrated acceptable safety with no procedural complications and acceptable efficacy with low rates of residual shunting at three-month follow-up.