Transcatheter Edge-to-Edge Repair for Acute Papillary Muscle Rupture After Transvenous Lead Extraction in a d-TGA

We present a case of a patient known for dextrotransposition of the great arteries corrected with a Mustard procedure, in whom severe mitral valve regurgitation secondary to transvenous lead extraction was successfully repaired with transcatheter edge-to-edge repair using the TriClip device (Abbott Vascular).

Clinical Heart fAilure Management Program: Changing the practice by partnering primary care and specialists (CHAMP-HF)

Background

While significant gains were made in the management of heart failure (HF), most patients are still diagnosed when they are acutely ill in hospital, often with advanced disease. Earlier diagnosis in the community could lead to improved outcomes. Whether a partnership and an educational program for primary care providers (PCP) increase HF awareness and management is unknown.

Methods

We conducted an observational study between March 2019 and June 2020 during which HF specialists gave monthly HF conferences to PCP. Using a pre-post design, medical charts and administrative databases were reviewed and a questionnaire was completed by participating PCP. Primary and secondary endpoints included: 1) the number of patients diagnosed with HF, 2) implementation of GDMT for patients with HFrEF; 3) PCPs' experience and confidence.

Results

Six PCP agreed to participate. Amongst the 11,909 patients of the clinic, 70 (0.59 %) patients met the criteria for HF. This number increased by 28.6 % (n = 90) after intervention. Increased use of GDMT for HFrEF patients at baseline (n = 35) was observed for all class of agents, with doubling of patients on triple therapies, from 8 (22.9 %) to 16 (45.7 %), p = 0.0047. Self-confidence on HF management was low (1, 16.7 %) but increased after the educational intervention of physicians (3, 50 %).

Conclusion

An educational and collaborative approach between HF specialists and community PCP increased the number of new HF cases diagnosed, enhanced implementation of GDMT in patients with HFrEF and increase PCPs' confidence in treating HF, despite being conducted during the COVID-19 pandemic.

Large scale genome-wide association analyses identify novel genetic loci and mechanisms in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an important cause of morbidity and mortality with both monogenic and polygenic components. We here report results from the largest HCM genome-wide association study (GWAS) and multi-trait analysis (MTAG) including 5,900 HCM cases, 68,359 controls, and 36,083 UK Biobank (UKB) participants with cardiac magnetic resonance (CMR) imaging. We identified a total of 70 loci (50 novel) associated with HCM, and 62 loci (32 novel) associated with relevant left ventricular (LV) structural or functional traits. Amongst the common variant HCM loci, we identify a novel HCM disease gene, SVIL, which encodes the actin-binding protein supervillin, showing that rare truncating SVIL variants cause HCM. Mendelian randomization analyses support a causal role of increased LV contractility in both obstructive and non-obstructive forms of HCM, suggesting common disease mechanisms and anticipating shared response to therapy. Taken together, the findings significantly increase our understanding of the genetic basis and molecular mechanisms of HCM, with potential implications for disease management.

The Evolution of Transcatheter Therapies for Mitral Valve Disease: From Mitral Valvuloplasty to Transcatheter Mitral Valve Replacement

The prevalence of mitral valve disease has evolved over the past 5 decades from primarily a disease of rheumatic origin to a disease affecting the aging population that encompasses a range of phenotypes from rheumatic mitral stenosis, degenerative mitral regurgitation, and degenerative mitral valve calcification to secondary mitral regurgitation. A reflection on the history of therapy for mitral valve disease is an expedition that follows the birth and development of structural heart intervention from the first percutaneous balloon mitral valvuloplasty to innovative technologies for transcatheter mitral valve repair and replacement. This review will lead you along this journey, pause to acknowledge the feats accomplished, and reflect on the road that lies ahead.

Early benefits of bariatric surgery on subclinical cardiac function: Contribution of visceral fat mobilization

AIMS

We explored the early effects of bariatric surgery on subclinical myocardial function in individuals with severe obesity and preserved left ventricular (LV) ejection fraction.

METHODS

Thirty-eight patients with severe obesity [body mass index (BMI) ≥35 kg/m²] and preserved LV ejection fraction (≥50%) who underwent bariatric surgery (biliopancreatic diversion with duodenal switch [BPD-DS]) (Surgery group), 19 patients with severe obesity managed with usual care (Medical group), and 18 age and sex-matched non-obese controls (non-obese group) were included. Left ventricular global longitudinal strain (LV GLS) was evaluated with echocardiography speckle tracking imaging. Abnormal myocardial function was defined as LV GLS <18%.

RESULTS

Age of the participants was 42 ± 11 years with a BMI of 48 ± 8 kg/m² (mean ± standard deviation); 82% were female. The percentage of total weight loss at 6 months after bariatric surgery was 26.3 ± 5.2%. Proportions of hypertension (61 vs. 30%, P = 0.0005), dyslipidemia (42 vs. 5%, P = 0.0001) and type 2 diabetes (40 vs. 13%, P = 0.002) were reduced postoperatively. Before surgery, patients with obesity displayed abnormal subclinical myocardial function vs. non-obese controls (LV GLS, 16.3 ± 2.5 vs. 19.6 ± 1.7%, P < 0.001). Six months after bariatric surgery, the subclinical myocardial function was comparable to non-obese (LV GLS, 18.2 ± 1.9 vs. 19.6 ± 1.7%, surgery vs. non-obese, P = NS). On the contrary, half of individuals with obesity managed medically worsened their myocardial function during the follow-up (P = 0.002). Improvement in subclinical myocardial function following bariatric surgery was associated with changes in abdominal visceral fat (r = 0.43, P < 0.05) and inflammatory markers (r = 0.45, P < 0.01), whereas no significant association was found with weight loss or change in insulin sensitivity (HOMA-IR) (P > 0.05). In a multivariate model, losing visceral fat mass was independently associated with improved subclinical myocardial function.

CONCLUSIONS

Bariatric surgery was associated with significant improvement in the metabolic profile and in subclinical myocardial function. Early improvement in subclinical myocardial function following bariatric surgery was related to a greater mobilization of visceral fat depot, linked to global fat dysfunction and cardiometabolic morbidity.

Optimizing Timing of Valve Intervention in Patients With Asymptomatic Severe Valvular Heart Disease

The management of valvular heart disease has changed dramatically over the past decade with advances in cardiac imaging, the use of novel biomarkers, and the development of transcatheter valve repair and replacement technology. International society guidelines have kept pace to provide recommendations for diagnosis, follow-up, and timing of intervention. The most challenging patient cohort for clinicians are patients with asymptomatic severe disease in whom the optimal timing of intervention can be ill-defined. It is a fine balance between the risks of early intervention on asymptomatic patients and improving patient outcomes by preventing long-term cardiac complications. The key in optimal patient management is gathering the necessary information on patient risk and combining that with the risk, efficacy, and durability of valve interventions to arrive at the appropriate timing for intervention. This group of patients will be the focus of this review as we delve into the natural history, recommended follow-up, and indications for intervention in patients with degenerative aortic and mitral valve disease.

Initial clinical experience with VersaCross transseptal system for transcatheter mitral valve repair

OBJECTIVES

The aim of this study is to describe the initial experience with versacross transseptal (TS) system for transseptal puncture for the transcatheter mitral valve repair using the MitraClip device.

BACKGROUND

Transeptal puncture is a key step in transcatheter mitral valve repair (MVR) and the use of the VersaCross system comprised of a sheath, a dilator and a radiofrequency wire has not been previously described.

METHODS

Prospective single center study of consecutive patients undergoing transcatheter mitral valve repair with the MitraClip device were included. Targeted TS puncture was performed under transesophageal echocardiographic (TEE) guidance. Baseline demographics, procedural characteristics, and major adverse procedural events were collected.

RESULTS

Twenty-five consecutive patients underwent transseptal puncture using the VersaCross TS system. Transseptal puncture was successful in 100% of patients. The mean time for TS puncture was 3 3 ± 1.6 min with no major adverse procedural events. The mean time from insertion of the VersaCross system to insertion of the MitraClip guide catheter was 3.8 ± 3.0 minutes.

CONCLUSION

The VersaCross TS system was successful in all patients for MitraClip procedure with no adverse procedural events and may be associated with increased procedural efficiency.

A Right Atrial Mass as Initial Presentation of a Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is recognized to have a strong tendency for vascular invasion. However, right atrial (RA) involvement is uncommon. It has been principally described as a fortuitous discovery during oncology follow-up or as an autopsy finding of patients with known HCC. We present a case of a patient whose initial HCC presentation was an RA mass found during a dyspnea investigation. Thereby, on the basis of this new finding, clinicians should consider HCC in their differential diagnosis when discovering an RA mass.

Septal myectomy in the era of genetic testing

BACKGROUND

Hypertrophic obstructive cardiomyopathy (HOCM) is one of the most common genetic cardiac diseases and encompasses an array of clinical presentations. Little is known about the impact of genetic background on outcomes after septal myectomy (SM). The aim of this study was to evaluate the effect of specific genetic mutations on midterm outcomes in adults undergoing SM for HOCM.

METHODS

From 2003 to 2020, a total of 59 patients (male = 66%, mean age = 52 ± 13) underwent SM after a preoperative genetic test. Patients were divided into two groups according to their test result (positive or negative). Preoperative echocardiograms were examined to identify phenotypical characteristics of each mutation.

RESULTS

A total of thirty-one patients (53%) had a positive genetic test. MYBPC3 was the most common mutation (15/31 patients). Four different phenotypes were identified on preoperative echocardiograms. Overall, Type 1 phenotype was the most common (37% of the cohort). Type 3 was found exclusively in patients with a positive genetic test. Following SM, none of the patients required a redo myectomy or septal ablation. At 10 years, the survival was 97 ± 3% and 100% in patients with a positive and negative genetic test (p = .33), respectively.

CONCLUSION

Although our results suggest that the multiple gene mutations present with different characteristics and phenotypes, midterm results of SM appear to be good regardless of genetic mutation presence.

Shared genetic pathways contribute to risk of hypertrophic and dilated cardiomyopathies with opposite directions of effect

The heart muscle diseases hypertrophic (HCM) and dilated (DCM) cardiomyopathies are leading causes of sudden death and heart failure in young, otherwise healthy, individuals. We conducted genome-wide association studies and multi-trait analyses in HCM (1,733 cases), DCM (5,521 cases) and nine left ventricular (LV) traits (19,260 UK Biobank participants with structurally normal hearts). We identified 16 loci associated with HCM, 13 with DCM and 23 with LV traits. We show strong genetic correlations between LV traits and cardiomyopathies, with opposing effects in HCM and DCM. Two-sample Mendelian randomization supports a causal association linking increased LV contractility with HCM risk. A polygenic risk score explains a significant portion of phenotypic variability in carriers of HCM-causing rare variants. Our findings thus provide evidence that polygenic risk score may account for variability in Mendelian diseases. More broadly, we provide insights into how genetic pathways may lead to distinct disorders through opposing genetic effects.

Care Gaps in Adherence to Heart Failure Guidelines: Clinical Inertia or Physiological Limitations?

OBJECTIVES

This study evaluated the impact of clinical and physiological factors limiting treatment optimization toward recommended medical therapy in heart failure (HF).

BACKGROUND

Although guidelines aim to assist physicians in prescribing evidence-based therapies and to improve outcomes of patients with HF and reduced ejection fraction (HFrEF), gaps in clinical care persist.

METHODS

Medical records of all patients with HFrEF followed for at least 6 months at the authors' HF clinic (n = 511) allowed for drug optimization and were reviewed regarding the prescription rates of recommended pharmacological agents and devices (implantable cardioverter-defibrillator [ICD] or cardiac resynchronization therapy [CRT]). Then, an algorithm integrating clinical (New York Heart Association [NYHA] functional class, heart rate, blood pressure and biologic parameters (creatinine, serum potassium) based on the inclusion/exclusion criteria of landmark trials guiding these recommendations) was applied for each agent and device to identify potential explanations for treatment gaps.

RESULTS

Gross prescription rates were high for beta-blockers (98.6%), mineralocorticoid receptor antagonist (MRA) (93.4%), vasodilators (90.3%), ICDs (75.1%), and CRT (82.1%) among those eligible, except for ivabradine (46.3%, n = 41). However, achievement of target physiological doses was lower (beta-blockers, 67.5%; MRA, 58.9%; and vasodilators, 63.4%), and one-fifth of patient dosages were still being up-titrated. Suboptimal doses were associated with older age (odds ratio [OR]: 1.221; p < 0.0001) and history of stroke or transient ischemic attack (TIA) (no vs. yes, OR: 0.264; p = 0.0336).

CONCLUSIONS

Gaps in adherence to guidelines exist in specialized HF setting and are mostly explained by limiting physiological factors rather than inertia. Older age and history of stroke/TIA, potential markers of frailty, are associated with suboptimal doses of guideline-directed medical therapy, suggesting that an individualized rather than a "one-size-fits-all" approach may be required.

Percutaneous transmitral balloon commissurotomy using a single balloon with arteriovenous loop stabilisation: an alternative when there is no Inoue balloon

Background

The Inoue balloon technique is the standard technique for mitral valve balloon commissurotomy at this stage. However, the hardware for this technique is expensive and may not always be available in resource-limited settings.

Objectives

This article reports our experience with percutaneous transmitral balloon commissurotomy using a single balloon (Nucleus) with arteriovenous loop stabilisation.

Methods

Eleven young patients, aged 12–26 years and weighing 23–48 kg, underwent transmitral balloon commissurotomy using the described technique at our centre from April to May 2014.

Results

Mean fluoroscopy time was 22.6 ± 6.4 min (18.5– 30.0). Mean transmitral gradient decreased from 24.1 ± 5.9 (16–35) to 6.6 ± 3.8 (3–14) mmHg, as measured on transoesophageal echocardiography. Mean mitral valve area increased from 0.69 ± 0.13 cm² (range 0.5–0.9) before dilation to 1.44 ± 0.25 cm² (1.1–1.9) after dilation (p < 0.001). Mean estimated pulmonary artery systolic pressure decreased from 110.0 ± 35 mmHg (75–170) before dilation to 28.0 ± 14.4 mmHg (range 10–60) after dilation.

Conclusion

Our modified Nucleus balloon technique for mitral valve dilation in young patients with mitral stenosis is effective and safe. The technique differs from other over-thewire techniques in that it avoids placing stiff wire in the left ventricle. It also offers better balloon stability and control owing to the arteriovenous loop. This technique may be easier for use by paediatric interventionists who might not be familiar with the Inoue balloon technique.

Transient Ischemic Dilatation during Stress Echocardiography: An Additional Marker of Significant Myocardial Ischemia

AIM

Left ventricular (LV) transient ischemic dilatation (TID) is not clear how it relates to inducible myocardial ischemia during stress echocardiography (SE).

METHODS AND RESULTS

Eighty-eight SEs were examined from the site certification phase of the ISCHEMIA Trial. LV end-diastolic volume (EDV) and end-systolic volume (ESV) were measured at rest and peak stages and the percent change calculated. Moderate or greater ischemia was defined as ≥3 segments with stress-induced severe hypokinesis or akinesis. Optimum cut points in stress-induced percent EDV and ESV change that identified moderate or greater myocardial ischemia were analyzed. Analysis from percentage distribution identified a > 13% LV volume increase in EDV or a > 9% LV volume increase in ESV as the optimum cutoff points for moderate or greater ischemia. Using these definitions for TID, there were 27 (31%) with TIDESV and 12 (14%) with TIDEDV . By logistic regression analysis and receiver operating characteristic curves, the percent change in ESV had a stronger association with moderate or greater myocardial ischemia than that of EDV change. Compared to those without TIDESV , cases with TIDESV had larger extent of inducible wall-motion abnormalities, lower peak stress LVEF, and higher likelihood of moderate or grater ischemia. For moderate or greater myocardial ischemia detection, TIDESV had a sensitivity of 46%, specificity of 83%, positive predictive value of 70%, and negative predictive value of 64%.

CONCLUSION

Transient ischemic dilatation by SE is a marker of extensive myocardial ischemia and can be used as an additional marker of higher risk.

Side-by-Side Comparison of LAA Occlusion Performance With the Amplatzer Cardiac Plug and Amplatzer Amulet

BACKGROUND

The Amplatzer Amulet, a second-generation device for left atrial appendage occlusion (LAAO), has been designed to facilitate the implantation process, improve the closure performance, and reduce the risk of complications. The objective of this study was to compare the outcomes of the Amplatzer Cardiac Plug (ACP) with the Amplatzer Amulet for LAAO, with a special focus on the incidence of residual leaks.

METHODS

This was a prospective, single-center review of consecutive patients undergoing percutaneous LAAO with either ACP or Amulet devices. The first transesophageal echocardiography (TEE) at follow-up (1-3 months) was utilized to assess the occurrence of residual leaks.

RESULTS

Between November 2009 and August 2013, a total of 59 patients underwent LAAO with either the ACP device (n = 31) or Amulet device (n = 28). The device was successfully implanted in 58 patients (98.3%). There was no procedural device embolization, stroke, or cardiac tamponade. Follow-up TEE was available in 86% (50 patients; 25 ACP devices and 25 Amulet devices). At follow-up, there was no procedural device embolization, and only 1 patient who received an Amulet device presented with device thrombosis at follow-up. Amulet use was associated with a significant reduction of any leak (minor, moderate, or major) compared with ACP use (48% ACP vs 8% Amulet; P=.01).

CONCLUSION

In this initial series, the Amulet showed similar procedural and short-term clinical outcomes compared with the ACP. The Amulet was, however, associated with a significant reduction of residual leaks at follow-up.

Magnetic Resonance Imaging of Hypertrophic Cardiomyopathy: Beyond Left Ventricular Wall Thickness

During the past decade, cardiac magnetic resonance has gained increasing popularity in the diagnosis of hypertrophic cardiomyopathy because of its greater accuracy and better characterization of cardiac morphology compared with other imaging modalities. In this pictorial essay, a global clinical portrait of hypertrophic cardiomyopathy will be drawn. The various radiologic findings associated with each variant of hypertrophic cardiomyopathy, and the clinical edge offered by cardiac magnetic resonance will be discussed.

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.

Intra-procedural imaging of the left atrial appendage: implications for closure with the Amplatzer™ cardiac plug

OBJECTIVES

To evaluate intra-procedural imaging with transesophageal echocardiography and angiography during left atrial appendage occlusion using the Amplatzer™ Cardiac Plug with regard to sizing and final device shape.

METHODS

Left atrial appendage ostium dimensions and diameter at a depth of 10mm from the ostium were measured by transesophageal echocardiography (0-180°) and angiography (RAO 30° - Cranial 20°) in consecutive patients undergoing left atrial appendage occlusion using the ACP with an oversizing strategy of 10-20% relative to the baseline measurements. After delivery, ACP dimensions were measured and device shape was assessed.

RESULTS

Twenty-seven consecutive patients underwent successful uncomplicated left atrial appendage closure with Amplatzer™ Cardiac Plug. We found a significant difference between the largest and smallest left atrial appendage diameter measured with transesophageal echocardiography (22.3±4.2 vs. 18.1±4.1mm, p<0.001). By the end of the procedure (by angiography), ACP had an optimal shape in 17 patients (63%), a strawberry-like shape in 7 patients (26%), and a square-like shape in 3 patients (11%). ACP was oversized on average by 1.5±2.7 and 3.3±2.3mm compared to transesophageal echocardiography and angiography, respectively. The final shape of the device was not significantly associated with the degree of oversizing.

CONCLUSIONS

We found a considerable variability in the assessment of the left atrial appendage, using transesophageal echocardiography and angiography. The degree of Amplatzer™ Cardiac Plug expansion within the left atrial appendage and the final shape of the device were not associated with the degree of oversizing.

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.

Multiplanar transesophageal echocardiography for the evaluation and percutaneous management of ostium secundum atrial septal defects in the adult

The purpose of this paper is to review the usefulness of multiplanar transesophageal echocardiography before, during and after percutaneous transcatheter closure of secundum atrial septal defects. Transesophageal echocardiography imaging techniques,including their role in patient selection, procedural guidance and immediate assessment of technical success and complications are described and discussed in this review. Percutaneous transcatheter closure is indicated for ostium secundum atrial septal defects of less than 40 mm in maximal diameter. The defect must have a favorable anatomy, with adequate rims of at least 5 mm to anchor the prosthesis. Transesophageal echocardiography plays a critical role before the procedure in identifying potential candidates for percutaneous closure and to exclude those with unfavorable anatomy or associated lesions, which could not be addressed percutaneously. Transesophageal echocardiography is also important during the procedure to guide the deployment of the device. After device deployment, the echocardiographer must assess the device (integrity, position and stability), residual shunt, atrio-ventricular valve regurgitation, obstruction to systemic or venous return and pericardial effusion, in order to determine procedural success and diagnose immediate complications.

Impact of mitral regurgitation and myocardial viability on left ventricular reverse remodeling after cardiac resynchronization therapy in patients with ischemic cardiomyopathy

This study investigated the impact of ischemic mitral regurgitation (MR) severity and viability on left ventricular (LV) reverse remodeling after cardiac resynchronization therapy (CRT) in patients with ischemic cardiomyopathy. Severe MR and ischemic cardiomyopathy have been associated with lack of LV reverse remodeling after CRT. Fifty-seven consecutive patients with ischemic MR, LV ejection fraction < or =35%, QRS duration > or =120 ms, and intraventricular dyssynchrony > or =50 ms were prospectively included. Stress echocardiography was performed before CRT implantation. Viability in the region of the LV pacing lead was defined as the presence of viability in 2 contiguous segments. Response to CRT at 6 months was defined by evidence of > or =15% LV decrease in end-systolic volume. Severe MR was defined by an effective regurgitant orifice (ERO) area > or =20 mm(2). Thirty-three patients (58%) were responders at follow-up. Baseline ERO area and prevalence of severe MR were not different between responders and nonresponders (19 +/- 11 vs 21 +/- 13 mm(2), p = 0.67; 52% vs 53%, p = 0.84). In responders, MR was decreased by 58% (ERO 19 +/- 12 to 8 +/- 6 mm(2)). In the presence of viability in the region of the pacing lead, 74% (n = 29 patients) were responders (sensitivity 88%, specificity 58%); in the subgroup of patients with viability in the region of the pacing lead and severe MR, 83% (n = 17 patients) were responders. In conclusion, LV remodeling is frequent and ischemic MR decrease important in patients with viability in the region of the pacing lead without regard to MR severity.

Usefulness and limitation of dobutamine stress echocardiography to predict acute response to cardiac resynchronization therapy

BACKGROUND

It has been hypothesized that a long-term response to cardiac resynchronization therapy (CRT) could correlate with myocardial viability in patients with left ventricular (LV) dysfunction. Contractile reserve and viability in the region of the pacing lead have not been investigated in regard to acute response after CRT.

METHODS

Fifty-one consecutive patients with advanced heart failure, LV ejection fraction <or= 35%, QRS duration > 120 ms, and intraventricular asynchronism >or= 50 ms were prospectively included. The week before CRT implantation, the presence of viability was evaluated using dobutamine stress echocardiography. Acute responders were defined as a >or=15% increase in LV stroke volume.

RESULTS

The average of viable segments was 5.8 +/- 1.9 in responders and 3.9 +/- 3 in nonresponders (P = 0.03). Viability in the region of the pacing lead had an excellent sensitivity (96%), but a low specificity (56%) to predict acute response to CRT. Mitral regurgitation (MR) was reduced in 21 patients (84%) with acute response. The presence of MR was a poor predictor of response (sensibility 93% and specificity 17%). However, combining the presence of MR and viability in the region of the pacing lead yields a sensibility (89%) and a specificity (70%) to predict acute response to CRT.

CONCLUSION

Myocardial viability is an important factor influencing acute hemodynamic response to CRT. In acute responders, significant MR reduction is frequent. The combined presence of MR and viability in the region of the pacing lead predicts acute response to CRT with the best accuracy.

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.

Epstein-Barr virus polymerase chain reaction-negative stage IV post-transplant lymphoproliferative disorder in a heart transplant patient treated with rituximab

Post-transplant lymphoproliferative disorder (PTLD) is often associated with Epstein-Barr virus (EBV). However, in this report, we describe a heart transplant recipient with pathologically proven EBV-positive PTLD with undetectable virus by polymerase chain reaction. The patient had remission after anti-CD20 antibody treatment early after transplantation.

Times to Treatment in Patients Undergoing Primary Percutaneous Coronary Intervention at Laval Hospital

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 minfor transferred patients with no more than 4 % of patients treated within 90 min. We conducted this retrospective observational study to assess time to treatment in patients undergoing primary PCI at Quebec Heart and Lung Institute (QHLI). Methods: Consecutive lytic-eligible patients undergoing primary PCI at QHLI for STEMI between April 2004 and March 2004 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 consisted of in-hospital death, reinfarction and bleeding. DTB times and hospital outcomes of patients transferred from referring hospitals were compared to patients presenting directly to QHLI. Results: During the study period, 203 lytic-eligible patients were treated with primary PCI and included in the present analysis. Sixty-nine patients presented directly to QHLI and 134 were transferred from other Quebec City hospitals. The median DTB time was 114 min in transferred patients, compared with 87 min for patients presenting directly to QHLI [P < 0.001]. DTB time was

Investigation of muscle recruitment patterns in scoliosis using a biomechanical finite element model

The objective of this project is to study the characteristics of trunk muscle recruitment strategies experimentally observed for scoliotic subjects using a finite element model of the trunk. The personalized biomechanical model includes elements representing the osseo-ligamentous structures of the spine, rib cage and pelvis. It also integrates the principal agonistic muscles necessary for trunk movement and a neural control model based on the Equilibrium Point hypothesis (lambda model of Feldman). Muscle recruitment patterns of normal and scoliotic subjects obtained from the simulation of lateral bending movements were qualitatively compared. The generation process of motor control variables was studied by analysing the relationships between central commands and spine segment mobility. Differences in recruitment patterns between normal and scoliotic subjects were observed, especially for paraspinal fascicles crossing the thoracic curve segment. The generation of central commands for normal subjects was strongly correlated with the amplitude of bending, but this relation was weaker for scoliotic subjects and this difference was worst at the apex vertebra. These results show that neuromuscular disorders could occur at a local level. The proposed approach should provide a simulation tool to study the multifactorial origin of scoliosis, and to investigate the implication of muscles and central commands in spinal dysfunctions.