Philippe B. Bertrand

Mitral valve area during exercise after restrictive mitral valve annuloplasty: importance of diastolic anterior leaflet tethering.

BACKGROUND Restrictive mitral valve annuloplasty (RMA) for secondary mitral regurgitation might cause functional mitral stenosis, yet its clinical impact and underlying pathophysiological mechanisms remain debated. OBJECTIVES The purpose of our study was to assess the hemodynamic and clinical impact of effective orifice area (EOA) after RMA and its relationship with diastolic anterior leaflet (AL) tethering at rest and during exercise. METHODS Consecutive RMA patients (n = 39) underwent a symptom-limited supine bicycle exercise test with Doppler echocardiography and respiratory gas analysis. EOA, transmitral flow rate, mean transmitral gradient, and systolic pulmonary arterial pressure were assessed at different stages of exercise. AL opening angles were measured at rest and peak exercise. Mortality and heart failure readmission data were collected for at least 20 months after surgery. RESULTS EOA and AL opening angle were 1.5 ± 0.4 cm(2) and 68 ± 10°, respectively, at rest (r = 0.4; p = 0.014). EOA increased significantly to 2.0 ± 0.5 cm(2) at peak exercise (p < 0.001), showing an improved correlation with AL opening angle (r = 0.6; p < 0.001). Indexed EOA (EOAi) at peak exercise was an independent predictor of exercise capacity (maximal oxygen uptake, p = 0.004) and was independently associated with freedom from all-cause mortality or hospital admission for heart failure (p = 0.034). Patients with exercise EOAi <0.9 cm(2)/m(2) (n = 14) compared with ≥0.9 cm(2)/m(2) (n = 25) had a significantly worse outcome (p = 0.048). In multivariate analysis, AL opening angle at peak exercise (p = 0.037) was the strongest predictor of exercise EOAi. CONCLUSIONS In RMA patients, EOA increases during exercise despite fixed annular size. Diastolic AL tethering plays a key role in this dynamic process, with increasing AL opening during exercise being associated with higher exercise EOA. EOAi at peak exercise is a strong and independent predictor of exercise capacity and is associated with clinical outcome. Our findings stress the importance of maximizing AL opening by targeting the subvalvular apparatus in future repair algorithms for secondary mitral regurgitation.

Global myocardial oedema in advanced decompensated heart failure.

Aims To use cardiac magnetic resonance (CMR) imaging with quantitative T2 mapping as surrogate for myocardial water content in patients with advanced decompensated heart failure (ADHF), compare these values with T2-values observed in chronic heart failure, and evaluate the change with decongestive therapy. Methods and Results Volumetric CMR measurements and quantitative T2 mapping were performed in 18 consecutive ADHF patients with clinical signs of volume overload. Eleven patients with stable heart failure were used as controls. Vasodilator therapy and diuretics were administered to achieve a pulmonary arterial wedge pressure (PAWP) of <18 mmHg and central venous pressure (CVP) of <12 mmHg, after which CMR was repeated. ADHF patients (62 ± 12 years; 89% male; left ventricular ejection fraction 23 ± 8%) presented with low cardiac index (2.08 ± 0.59 L/min/m2), high PAWP (25 ± 7 mmHg), and high CVP (14 ± 5 mmHg). After decongestion, the patients had a significant increase in cardiac index (+0.41 ± 0.53 L/min/m2; P = 0.005) and decreases in both PAWP (−9 ± 6 mmHg; P < 0.001) and CVP (−6 ± 5 mmHg; P < 0.001). At baseline, global left ventricular T2-values were higher in ADHF patients compared with controls (59.5 ± 4.6 vs. 54.7 ± 2.2 ms, respectively; P = 0.001). After decongestion, T2-values fell significantly to 55.9 ± 5.1 ms (P = 0.001), comparable with controls (P = 0.580). In contrast, psoas muscle T2-values were similar at baseline (38.6 ± 4.4 ms) vs. after decongestion (37.8 ± 4.8 ms; P = 0.397). Each 1 ms decrease in global left ventricular T2-value during decongestion was associated with a 1.14 ± 0.40 mmHg decrease in PAWP (P = 0.013), after correction for age and gender. Conclusion Patients presenting with ADHF and volume overload have increased global left ventricular—but not psoas muscle—T2-values, which decrease with successful decongestion. Relief of myocardial oedema correlates with haemodynamic unloading.

Fact or Artifact in Two-Dimensional Echocardiography: Avoiding Misdiagnosis and Missed Diagnosis

Two-dimensional transthoracic echocardiography is the most widely used noninvasive imaging modality for the evaluation and diagnosis of cardiac pathology. However, because of the physical properties of ultrasound waves and specifics in ultrasound image reconstruction, cardiologists are often confronted with ultrasound image artifacts. It is particularly important to recognize such artifacts in order to avoid misdiagnosis of conditions ranging from aortic dissection to thrombosis and endocarditis. This overview article summarizes the most common image artifacts encountered in routine clinical practice, along with explanations of their physical mechanisms and guidance in avoiding their misinterpretation.

Plasma Volume Is Normal but Heterogeneously Distributed, and True Anemia Is Highly Prevalent in Patients With Stable Heart Failure

BACKGROUND Intravascular volume overload and depletion as well as anemia are associated with increased hospital admissions and mortality in patients with heart failure. This study aimed to accurately measure plasma volume and red cell mass (RCM) in stable patients with chronic heart failure with reduced ejection fraction (HFrEF) and gain more insight into plasma volume regulation and anemia in stable conditions of HFrEF. METHODS AND RESULTS Plasma volume and RCM measurement based on 99Tc-labeled red blood cells, venous blood sample,s and clinical parameters were obtained in 24 stable HFrEF patients under optimal medical therapy. Measured plasma volume values were compared with predicted values based on body surface area. Plasma volume was on average normal (99.98% of predicted) but heterogeneously distributed (variations of 81%-133%). Neurohumoral activation and medication use were not associated with plasma volume status. Furthermore, anemia based on actual measurement of RCM was present in up to 75% of subjects, but rarely hemodilutional. CONCLUSIONS In stable chronic HFrEF patients under optimal medical therapy, plasma volume is overall normal but heterogeneously distributed. Anticipated factors such as neurohumoral activation and heart failure medication were not associated with plasma volume. Furthermore, anemia is more common than as assessed by hemoglobin.

Exercise Dynamics in Secondary Mitral Regurgitation Pathophysiology and Therapeutic Implications

Secondary mitral valve regurgitation (MR) remains a challenging problem in the diagnostic workup and treatment of patients with heart failure. Although secondary MR is characteristically dynamic in nature and sensitive to changes in ventricular geometry and loading, current therapy is mainly focused on resting conditions. An exercise-induced increase in secondary MR, however, is associated with impaired exercise capacity and increased mortality. In an era where a multitude of percutaneous solutions are emerging for the treatment of patients with heart failure, it becomes important to address the dynamic component of secondary MR during exercise as well. A critical reappraisal of the underlying disease mechanisms, in particular the dynamic component during exercise, is of timely importance. This review summarizes the pathophysiological mechanisms involved in the dynamic deterioration of secondary MR during exercise, its functional and prognostic impact, and the way current treatment options affect the dynamic lesion and exercise hemodynamics in general.

Pulmonary vascular response to exercise in symptomatic heart failure with reduced ejection fraction and pulmonary hypertension

To study pulmonary vascular response patterns to exercise in heart failure with reduced ejection fraction (HFrEF) and pulmonary hypertension (PH).

Etiology and Relevance of the Figure-of-Eight Artifact on Echocardiography after Percutaneous Left Atrial Appendage Closure with the Amplatzer Cardiac Plug

BACKGROUND The Amplatzer Cardiac Plug (ACP) device, used for percutaneous left atrial appendage closure, frequently presents as an unexplained figure-of-eight on echocardiography. The aim of this study was to clarify the figure-of-eight display of the ACP device during echocardiography and to relate this finding to device position and function. METHODS A mathematical model was developed to resemble device geometry and predict the echocardiographic appearance of the ACP device. In addition, an in vitro setup was used to validate the model. Finally, echocardiographic images of consecutive patients referred for percutaneous left atrial appendage closure (n = 24) were analyzed for the presence of a figure-of-eight display. RESULTS Because the ACP device resembles an epitrochoid curve, those points with tangent vector perpendicular to the ultrasound waves are emphasized, resulting in a figure-of-eight display, which can be replicated in vitro in the coronal imaging position. We found the figure-of-eight display in 100% (11 of 11) of three-dimensional periprocedural transesophageal images and in 87% (34 of 39) of postprocedural transthoracic echocardiographic images. CONCLUSIONS The figure-of-eight display of the ACP device during echocardiography is the result of the specific epitrochoid geometry of the device mesh and its interaction with ultrasound waves. It is important to recognize the figure-of-eight as being a normal imaging artifact of a correctly deployed device in the coronal imaging position on both transesophageal and transthoracic echocardiography. In the future, this could be used during follow-up to aid clinical practitioners in assessing device position and function.

Feasibility and Association of Neurohumoral Blocker Up-titration After Cardiac Resynchronization Therapy

BACKGROUND Cardiac resynchronization therapy (CRT) improves mortality and morbidity on top of optimal medical therapy in heart failure with reduced ejection fraction (HFrEF). This study aimed to elucidate the association between neurohumoral blocker up-titration after CRT implantation and clinical outcomes. METHODS AND RESULTS Doses of angiotensin-converting enzyme inhibitors (ACE-Is), angiotensin receptor blockers (ARBs), and beta-blockers were retrospectively evaluated in 650 consecutive CRT patients implanted from October 2008 to August 2015 and followed in a tertiary multidisciplinary CRT clinic. All 650 CRT patients were on a maximal tolerable dose of ACE-I/ARB and beta-blocker at the time of CRT implantation. However, further up-titration was successful in 45.4% for ACE-I/ARB and in 56.8% for beta-blocker after CRT-implantation. During a mean follow-up of 37 ± 22 months, a total of 139 events occurred for the combined end point of heart failure admission and all-cause mortality. Successful, versus unsuccessful, up-titration was associated with adjusted hazard ratios of 0.537 (95% confidence interval 0.316-0.913; P = .022) for ACE-I/ARB and 0.633 (0.406-0.988; P = .044) for beta-blocker on the combined end point heart failure admission and all-cause mortality. Patients in the up-titration group exhibited a similar risk for death or heart failure admission as patients treated with the maximal dose (ACE-I/ARB: P = .133; beta-blockers: P = .709). CONCLUSIONS After CRT, a majority of patients are capable of tolerating higher dosages of neurohumoral blockers. Up-titration of neurohumoral blockers after CRT implantation is associated with improved clinical outcomes, similarly to patients treated with the guideline-recommended target dose at the time of CRT implantation.

Mid-term results of leaflet augmentation in severe tricuspid functional tethering

OBJECTIVES Functional tricuspid regurgitation (FTR) is usually managed surgically using various types of annuloplasty. FTR has been reported to recur in up to 45% of patients, with severe leaflet tethering being an important risk factor for recurrence. The aim of this study is to report the clinical and echocardiographic mid-term results after leaflet augmentation in patients with FTR due to severe leaflet tethering. METHODS From May 2008 to July 2014, 22 patients were found to have a severe FTR with a tethering height of at least 8 mm; all of them underwent leaflet augmentation: the anterior and part of the posterior leaflet were detached from the anterior annulus; a patch of fresh autologous pericardium was used to generously fill the gap between the anterior annulus and the detached leaflet. A 5/0 Pronova suture locked at every step was used to avoid any purse string effect. In 2 patients, the septal leaflet also needed to be augmented using a comparable technique. In all but one (annular calcification) patient, a semi-rigid ring annuloplasty was added. The mean age was 67.1 ± 13.7 years; it was a redo procedure in 12 cases (54.5%), 11 patients (50%) had right ventricle failure and 3 (23.1%) had renal failure. RESULTS The median follow-up was 2.1 ± 1.9 years. Thirty-day and 4-year survival averaged at 81.1 ± 8.5 and 71.6 ± 9.8%, respectively. At 4 years, 84 ± 10.6% of the survivors were in NYHA class I or II and only 2 patients had a TR of ≥2 with a global freedom from TR ≥2 of 85.7 ± 13.2%. There was no reintervention. CONCLUSIONS Tricuspid leaflet augmentation combined with annuloplasty is feasible and leads to excellent clinical and echocardiographical mid-term results even in the presence of severe leaflet tethering and right ventricular failure.

The Figure-of-Eight Artifact in the Echocardiographic Assessment of Percutaneous Disc Occluders: Impact of Imaging Depth and Device Type

Echocardiography is increasingly important in the guidance and follow‐up of percutaneous transcatheter device closures. It was recently shown that the Amplatzer left atrial appendage occluder frequently presents as a figure‐of‐eight artifact due to interaction of device mesh and ultrasound waves. It remains unknown whether this can be translated to other types of disc occluders. Furthermore, the morphology of this figure‐of‐eight artifact appears to be different in the transesophageal and transthoracic image of the same device. The aim of this study was to evaluate the echocardiographic appearance of different types of disc occluders, and to clarify differences in morphology of the figure‐of‐eight artifact.