Frédéric Rouleau

Echocardiographic Assessment of the Interventricular Delay of Activation and Correlation to the QRS Width in Dilated Cardiomyopathy

ROULEAU, F., et al.: Echocardiographic Assessment of the Interventricular Delay of Activation and Correlation to the QRS Width in Dilated Cardiomyopathy. The aim of the study was to define criteria for left ventricular pacing in dilated cardiomyopathy (DCM) using an echocardiographic evaluation of interventricular electromechanical delay (IMD) and a correlation of IMD to QRS duration. Standard 12‐lead ECG and echocardiography with pulsed Doppler tissue imaging (DTI) were recorded in 35 DCM patients (mean age 58 ± 11 years) with QRS duration from narrow (80 ms) to broad (222 ms) patterns. The time for left ventricular activation was evaluated from the onset of QRS to the onset of aortic flow (Q‐Ao) by standard pulsed Doppler (SP) or to the onset of mitral annulus systolic wave (Q‐Mit) (DTI). The time for right ventricular activation was determined from the onset of QRS to the onset of pulmonary flow (Q‐Pulm) (SP) or to the onset of tricuspid annulus systolic wave (Q‐Tri) (DTI). (Q‐Ao)–(Q‐Pulm) and (Q‐Mit)–(Q‐Tri) determined IMD for each method, respectively. QRS width and IMD showed correlation coefficients of r = 0.86 ([Q‐Ao]‐[Q‐Pulm]) and r = 0.82 ([Q‐Mit]‐[Q‐Tri]) (P ≤ 0.001). Mean IMD of 77 ± 15 ms (SP) and 88 ± 26 ms (DTI) were noted for QRS width above 150 ms. Left ventricle delayed activation was positively correlated to QRS widening with both methods, (r = 0.90, [Q‐Ao]), (r = 0.83, [Q‐Mit]) (P ≤ 0.001). In conclusion, QRS duration is a good marker of an interventricular mechanical asynchrony. According to IMD correction, left ventricular pacing may be mainly proposed to symptomatic DCM patients with QRS duration > 150 ms.

Programming Optimal Atrioventricular Delay in Dual Chamber Pacing Using Peak Endocardial Acceleration: Comparison with a Standard Echocardiographic Procedure

DUPUIS, J.‐M., et al .: Programming Optimal Atrioventricular Delay in Dual Chamber Pacing Using Peak Endocardial Acceleration: Comparison with a Standard Echocardiographic Procedure. Optimization of programmed atrioventricular delay in dual chamber pacing is essential to the hemodynamic efficiency of the heart. Automatic AV delay optimization in an implanted pacemaker is highly desirable. Variations of peak endocardial acceleration (PEA) with AV delay at rest correlate well with echocardiography derived observations, particularly with end‐diastolic filling and mitral valve closure timings. This suggests the possibility of devising a procedure for the automatic determination of the optimal AV delay. The aim of this study was to compare a proposed algorithm for optimal AV delay determination with an accepted echocardiographic method. Fifteen patients with high degree AV block received BEST‐Living pacing systems. Automatic AV delay scans were performed at rest (60–300 ms in 20‐ms steps with 60 beats per step) in DDD at 90 ppm, while simultaneously recording cycle‐by‐cycle PEA values, which were averaged for each AV delay to obtain a PEA versus AV delay curve. Nonlinear regression analysis based on a Boltzmann sigmoid curve was performed, and the optimal AV delay (OAVD) was chosen as the sigmoid inflection point of the regression curve. The OAVD was also evaluated for each patient using the Ritter echocardiographic method. Good sigmoid fit was obtained in 13 of 15 patients. The mean OAVD obtained by the PEA sigmoid algorithm was 146.9 ± 32.1  ms , and the corresponding result obtained by echocardiography was 156.4 ± 34.3  ms (range 31.8–39.7 ms). Correlation analysis yielded r = 0.79, P = 0.0012. In conclusion, OAVD estimates obtained by PEA analysis during automatic AV delay scanning are consistent with those obtained by echocardiography. The proposed algorithm can be used for automatic OAVD determination in an implanted pacemaker pulse generator. (PACE 2003; 26:[Pt. II]:210–213)

Regional assessment of wall curvature and wall stress in left ventricle with magnetic resonance imaging

Left ventricular functional abnormalities are associated with regional increases of wall stress and modifications of wall curvature. This study describes the integration of the short-axis and long-axis wall curvatures for determining peak systolic wall stress. Quantification was realized with cine magnetic resonance imaging (MRI) from the location of the endocardial and epicardial borders of the left ventricle on pairs of consecutive short-axis sections. Fifteen normal volunteers were subjected to cine MRI, and different methods of calculating peak systolic wall stress were compared. A short-axis analysis showed a 55 +/- 13% increase of the circumferential mean of the peak systolic wall stress between apical and basal sections. Regarding the curvature, no significant increase of wall stress was observed except on the septal wall (31 +/- 18%). Short-axis studies proved to be insufficient for determining the regional variations of left ventricular wall stress and for providing normal reference values for the location of abnormal regions in patients.

GLOBAL LEFT VENTRICULAR CARDIAC FUNCTION : COMPARISON BETWEEN MAGNETIC RESONANCE IMAGING, RADIONUCLIDE ANGIOGRAPHY, AND CONTRAST ANGIOGRAPHY

RATIONALE AND OBJECTIVES Cardiac magnetic resonance imaging (MRI) has been shown to be a robust and noninvasive method to assess left ventricular (LV) cardiac function. This study sought to assess volumes and mass calculated with MRI using fast techniques for acquisition and postprocessing, and to compare results in terms of cost-effectiveness with those of radionuclide angiography (RNA) or contrast angiography (CA). METHODS Thirty-five patients and 15 healthy volunteers were studied. All patients underwent an MRI examination during the same period that they underwent ventriculography (26 patients) or radiography (25 patients). From 7 to 11 short-axis slices were acquired with a breath-hold fast-gradient echo-segmented sequence from apex to base. Contours were drawn with an automated border detection software. RESULTS Ejection fraction (EF) correlated well between modalities (r = 0.77, P<0.001, for MRI and RNA; r = 0.72, P< 0.001, for MRI and CA). CONCLUSIONS Cardiac MRI is a fast and accurate technique for estimation of LV volumes, EF, and mass.

CMR assessment after a transapical-transcatheter aortic valve implantation

AIMS To describe the time course of myocardial scarring after transapical-transcatheter aortic valve implantation (TA-TAVI) with the Edwards SAPIEN XT™ and the Edwards SAPIEN™ prosthesis in a 3-month follow-up study using cardiac magnetic resonance imaging (CMR). METHODS In 20 TA-TAVI patients, CMR was performed at discharge and 3 months (3M). Cine-MRI was used for left ventricular (LV) functional assessment, and late gadolinium enhancement (LGE) imaging was employed for detecting the presence of myocardial scarring. Special attention was given to any artifacts caused by the prosthesis, which were consequently defined using a three-grade artifact scale. RESULTS We systematically reported the presence of small LGE hyperintensity relating to the apical segment, with no variation found between discharge and 3M (2.8±1.6g vs. 2.35±1.1g). LV ejection fraction, end-diastolic, and end-systolic volumes did not significantly vary. A small area of apical akinesia was observed, with no improvement at follow-up. Whereas the Edwards SAPIEN XT™ prosthesis and the Edwards SAPIEN™ prosthesis are both constituted by metallic stenting structure, the Edwards SAPIEN™ was responsible for a larger signal void, thus potentially limiting the diagnostic performance of CMR. CONCLUSIONS CMR may be performed safely in the context of TA-TAVI. The presence of a very small apical infarction correlating with focal akinesia was observed. As expected, the Edwards SAPIEN XT™ prosthesis was shown to be particularly suitable for CMR assessment.

Myopericarditis complicated by pulmonary embolism in an immunocompetent patient with acute cytomegalovirus infection: a case report

BackgroundPrimary acute cytomegalovirus infection in immunocompetent patients is common worldwide. Infection is most often asymptomatic or occurs sub-clinically with a self-limited mononucleosis-like syndrome. More rarely, the infection may lead to severe organ complications with pneumonia, myocarditis, pericarditis, colitis and hemolytic anemia. Recent cases of cytomegalovirus-associated thrombosis have also been reported sporadically in the medical literature.Case presentationWe report here a case of simultaneous myopericarditis and pulmonary embolism in a 30-year-old man with no medical history. The patient was not immunocompromised. We discuss the possible role of acute cytomegalovirus infection in the induction of vascular damage and review relevant cases in the literature.ConclusionThrombosis in patients with acute cytomegalovirus infection may be more frequent than is generally thought. Physicians need to be aware of the possible association between acute cytomegalovirus and thrombosis in immunocompetent patients, especially in the presence of severe systemic infection, as our case illustrates.

La myocardite aiguë, un mode de révélation peu fréquent du phéochromocytome: Revue de la littérature à propos d’une observation

We report a 29-year-old woman with an acute myocarditis documented by MRI as presenting manifestation of a pheochromocytoma, and we review the literature.

Influence of stentless versus stented valves on ventricular remodeling assessed at 6 months by magnetic resonance imaging and long-term follow-up

BACKGROUND To compare the effect of stented versus stentless bioprostheses on left ventricular remodeling and assess their impact on long-term survival. METHODS From January 2002 to December 2009, 62 severe aortic stenosis patients without coronary artery disease were randomized for bioprosthetic aortic valve replacement. After randomization, a cross-over was possible based on intraoperative data. Ventricular remodeling was studied by cardiovascular magnetic resonance imaging six months after surgery. Long-term survival was assessed by telephone survey. RESULTS Thirty-five patients received a porcine Mosaïc® Medtronic bioprosthesis (Stented Group; Medtronic, Minneapolis, MN, USA) inserted using the usual supra-annular technique and 27 received a porcine Freestyle® Medtronic bioprosthesis (Stentless Group) inserted in the subcoronary position. Mean age was 75±3 and 73±4 years in the stentless and stented group, respectively. Nine patients who should have been implanted with a stentless bioprosthesis received a stented bioprosthesis for anatomical reasons. At 6 months, the left ventricular mass (LVM) decreased significantly in both groups (Stentless Group: 214.6±56.1g and 156.3±23g and Stented Group: 237±75.7g and 181±53.3g, respectively after surgery and at 6 months), this decrease was significantly greater in the stentless group (p=0.026). Reserve and coronary flow were increased in both groups at 6 months. Mean follow-up duration was 6.6±3.0 years and 7.2±4.0 years in the stentless and stented group, respectively. The 5-year actuarial survival was 87.5±11.7% and 82.5±17.1% for the stentless and stented group, respectively (p=0.81). CONCLUSION Porcine stentless prosthesis results in a better LVM regression than a stented valve at 6 months without changing the long-term survival.

0179: Transcatheter valve-in-valve implantation in patients with failed aortic bioprosthesis: immediate and medium-term outcomes of 15 procedures

Background TAVI offers an attractive option for patients with failed bioprosthesis and high operative risk (valve-in-valve concept). Purpose The objective of this study was to analyze outcomes of patients with failed aortic bioprosthesis undergoing transcatheter aortic valve-in-valve implantation. Methods From January 2012 to January 2015, 15 patients with degenerated aortic valve bioprosthesis underwent transcatheter aortic valve-in-valve implantation in our institution. Mean patient age was 82±6 years. Mean logistic Euroscore was 36±16% and mean STS score was 16±14%. The mean follow-up was 260±316 days. Results The failing bioprosthesis were Cryolife O’brien in 5 patients, Carpentier Edwards in 5 patients, Medtronic mosaic in 4 patients and Mitroflow in 1 patient. Bioprosthesis mode of failure was stenosis (n=6), regurgitation (n=5), or combined stenosis and regurgitation (n=4). The mean degenerative time was 11.15±6.1 years. Implanted devices included Medtronic CoreValve (n=6) and Edwards SAPIEN (n=9). Successful implantation of a transcatheter aortic valve-in-valve with the patient leaving the catheterization laboratory alive was achieved in all patients. Adverse procedural outcomes included initial device malposition in 3 cases requiring a second valve, retroperitoneal hematoma in 1 patient, permanent pacemaker in 1 patient, Stroke in 1 patient and acute renal failure in 1 patient. The mean transvalvular gradient passed from 48.7±17.63 to 18.32±9.3mmHg in stenotic degenerated bioprosthesis. No significant aortic regurgitation was observed post-implantation. During hospitalization, 1 patient developed myocardial infarction. The medium inhospital stay was 13.4±7.7 days. During later follow-up, there was no death, no myocardial infarction and no stroke or TIA. 2 patients were hospitalized for heart failure. Conclusion Transcatheter aortic valve-in-valve implantation seems to be feasible and safe in both stenotic and regurgitant degenerative bioprosthesis.