Martin Kotrc

Relationship of visually assessed apical rocking and septal flash to response and long-term survival following cardiac resynchronization therapy (PREDICT-CRT)

AIMS Apical rocking (ApRock) and septal flash (SF) are often observed phenomena in asynchronously contracting ventricles. We investigated the relationship of visually assessed ApRock and SF, reverse remodelling, and long-term survival in cardiac resynchronization therapy (CRT) candidates. METHODS AND RESULTS A total of 1060 patients eligible for CRT underwent echocardiographic examinations before and 12 ± 6 months after device implantation. Three blinded physicians were asked to visually assess the presence of ApRock and SF before device implantation and also their correction by CRT 12 ± 6 months post-implantation. Patients with a left ventricular (LV) end-systolic volume decrease of ≥15% during the first year of follow-up were regarded as responders. Patients were followed for a median period of 46 months (interquartile range: 27-65 months) for the occurrence of death of any cause. If corrected by CRT, visually assessed ApRock and SF were associated with reverse remodelling with a sensitivity of 84 and 79%, specificity of 79 and 74%, and accuracy of 82 and 77%, respectively. ApRock (hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.30-0.53, P < 0.0001) and SF (HR 0.45 [CI 0.34-0.61], P < 0.001) were independently associated with lower all-cause mortality after CRT and had an incremental value over clinical variables and QRS width for identifying CRT responders. Both the absence of ApRock/SF and unsuccessful correction of ApRock/SF despite CRT were associated with a high risk for non-response and an unfavourable long-term survival. CONCLUSION A specific LV mechanical dyssynchrony pattern, characterized by ApRock and SF, is associated with a more favourable long-term survival after CRT. Both parameters are also indicators of an effective therapy.

Lipolytic Effects of B-Type Natriuretic Peptide1–32 in Adipose Tissue of Heart Failure Patients Compared With Healthy Controls

OBJECTIVES Our goal was to examine the role of B-type natriuretic peptide (BNP) in lipolysis regulation in heart failure (HF) patients. BACKGROUND Enhanced adipose tissue lipolysis can contribute to myocardial lipid overload, insulin resistance, and cachexia in advanced HF. Natriuretic peptides were recently recognized to stimulate lipolysis in healthy subjects. METHODS Ten nondiabetic HF patients (New York Heart Association functional class III, 50% nonischemic etiology) and 13 healthy subjects (control subjects) of similar age, sex, and body composition underwent a microdialysis study of subcutaneous abdominal adipose tissue. Four microdialysis probes were simultaneously perfused with 0.1 μM BNP(1-32,) 10 μM BNP(1-32), 10 μM norepinephrine (NE) or Ringers solution. Outgoing dialysate glycerol concentration (DGC) was measured as an index of lipolysis. RESULTS Spontaneous lipolysis was higher in HF patients compared with control subjects (DGC: 189 ± 37 μmol/l vs. 152 ± 35 μmol/l, p < 0.01). Response to NE was similar (p = 0.35) in HF patients and control subjects (DGC increase of 1.7 ± 0.2-fold vs. 1.7 ± 0.4-fold). BNP(1-32) 10 μM markedly increased lipolysis in both HF patients and control subjects (DGC increase of 2.8 ± 0.5-fold vs. 3.2 ± 0.3-fold), whereas the response to 0.1 μM BNP(1-32) was more pronounced in HF patients (p = 0.02). In HF patients, spontaneous lipolysis positively correlated with insulin resistance and the response to BNP(1-32) negatively correlated with adiposity. CONCLUSIONS BNP(1-32) exerts strong lipolytic effects in humans. Despite marked elevation of plasma immunoreactive BNP, the responsiveness of adipose tissue to BNP(1-32) is not attenuated in HF, possibly reflecting a deficiency of endogenous bioactive BNP. Lipolytic effects of BNP can contribute to excessive fatty acid mobilization in advanced HF.

Association of Fibroblast Growth Factor-23 Levels and Angiotensin-Converting Enzyme Inhibition in Chronic Systolic Heart Failure.

OBJECTIVES The aim of this study was to evaluate the association of fibroblast growth factor (FGF)-23 with clinical and laboratory findings, the prognostic value of FGF-23, and the relationship between angiotensin-converting enzyme inhibitor (ACEi) therapy, FGF-23 levels, and outcomes in patients with chronic systolic heart failure (HF). BACKGROUND FGF-23 is a bone-derived hormone regulating mineral metabolism. Higher FGF-23 levels are associated with an increased risk of cardiovascular mortality or HF development. Mechanisms leading to increased FGF-23 and its prognostic value have not been thoroughly studied in HF. METHODS FGF-23 was measured in 369 patients (mean age 59 ± 11 years, 84% male) with systolic HF. Patients were followed for adverse events (e.g., death, urgent heart transplantation, ventricular assist device implantation). RESULTS Tricuspid regurgitation severity, chronic kidney disease (CKD), alkaline phosphatase concentrations, inferior vena cava dilation, and absence of ACEi therapy were independently associated with FGF-23. FGF-23 was independently associated with outcomes in patients without CKD (hazard ratio [HR]: 1.43, 95% confidence interval [CI]: 1.14 to 1.78), but not in CKD patients (HR: 1.12, 95% CI: 0.87 to 1.45). In patients without CKD and with FGF-23 in the highest tertile, ACEi therapy was associated with a lower risk of adverse events (HR: 0.42, 95% CI: 0.21 to 0.81), whereas no association was seen in the remaining patients (HR: 1.18, 95% CI: 0.52 to 2.70). CONCLUSIONS In systolic HF, elevated FGF-23 is an independent predictor of adverse events, particularly in patients with preserved renal function. The association of FGF-23 with adverse events likely reflects early alterations of renal hemodynamics and renin-angiotensin system activation. Increased FGF-23 may identify a subset of HF patients benefiting from ACEi therapy.

Resting heart rate and heart rate reserve in advanced heart failure have distinct pathophysiologic correlates and prognostic impact: A prospective pilot study

OBJECTIVES The purpose of this study was to compare the prognostic impact of clinical and biomarker correlates of resting heart rate (HR) and chronotropic incompetence in heart failure (HF) patients. BACKGROUND The mechanisms and underlying pathophysiological influences of HR abnormalities in HF are incompletely understood. METHODS In a prospective pilot study, 81 patients with advanced systolic HF (97% were receiving beta-blockers) and 25 age-, sex-, and body-size matched healthy controls underwent maximal cardiopulmonary exercise testing with sampling of neurohormones and biomarkers. RESULTS Two-thirds of HF patients met criteria for chronotropic incompetence. Resting HR and HR reserve (HRR, a measure of chronotropic response) were not correlated with each other and were associated with distinct biomarker profiles. Resting HR correlated with increased myocardial stress (B-type natriuretic peptide [BNP]: r = 0.26; pro-A-type natriuretic peptide: r = 0.24; N-terminal-proBNP: r = 0.32) and inflammation (leukocyte count: r = 0.28; high-sensitivity C-reactive protein assay: r = 0.25). In contrast, HRR correlated with the neurohumoral response to HF (copeptin: r = -0.33; norepinephrine: r = -0.29) but not with myocyte stress or injury reflected by natriuretic peptides or hs-troponin I. Patients in the lowest chronotropic incompetence quartile (HRR ≤0.38) displayed more advanced HF, reduced exercise capacity, ventilatory inefficiency, and poorer quality of life. Over a median follow-up of 17 months, the combined endpoint of death or urgent transplant/assist device implantation occurred more frequently in patients with higher resting HR (>67 beats/min) or lower HRR, with both markers providing additive prognostic information. CONCLUSIONS Increased resting HR and chronotropic incompetence may reflect different pathophysiological processes, provide incremental prognostic information, and represent distinct therapeutic targets.

Availability of energetic substrates and exercise performance in heart failure with or without diabetes

The goal of the study was to examine whether resting or post‐exercise metabolic substrate levels are associated with differential exercise performance and long‐term outcome in control subjects or heart failure (HF) patients with or without type 2 diabetes mellitus (DM).

Native T1 Relaxation Time and Extracellular Volume Fraction as Accurate Markers of Diffuse Myocardial Fibrosis in Heart Valve Disease – Comparison With Targeted Left Ventricular Myocardial Biopsy –

BACKGROUND The aim of our study was to investigate the relationship between the cardiac magnetic resonance (CMR)-derived native T1 relaxation time and myocardial extracellular volume (ECV) fraction and the extent of diffuse myocardial fibrosis (DMF) on targeted myocardial left ventricular (LV) biopsy. METHODSANDRESULTS The study population consisted of 40 patients (age 63±8 years, 65% male) undergoing valve and/or ascending aorta surgery for severe aortic stenosis (77.5%), root dilatation (7.5%) or valve regurgitation (15%). The T1 relaxation time was assessed in the basal interventricular septum pre- and 10-min post-contrast administration using the modified Look-Locker Inversion recovery sequence prior to surgery. LV myocardial biopsy specimen was obtained during surgery from the basal interventricular septal segment matched with the T1 mapping assessment. The percentage of myocardial collagen was quantified using picrosirius red staining. The average percentage of myocardial collagen was 22.0±14.8%. Both native T1 relaxation time with cutoff value ≥1,010 ms (sensitivity=90%, specificity=73%, area under the curve=0.82) and ECV with cutoff value ≥0.32 (sensitivity=80%, specificity=90%, area under the curve=0.85) showed high accuracy to identify severe (>30%) DMF. The native T1 relaxation time showed significant correlation with LV mass (P<0.01). CONCLUSIONS Native T1 relaxation time and ECV at 10 min after contrast administration are accurate markers of DMF. (Circ J 2016; 80: 1202-1209).

Percutaneous mitral valve repair in high-risk patients: initial experience with the Mitraclip system in Belgium.

Aims Treatment with percutaneous edge-to-edge mitral valve repair (Mitraclip®) has recently been recommended as an alternative to conventional mitral valve repair for high surgical risk patients with symptomatic severe mitral regurgitation (MR). In this study, we report the first use of Mitraclip® therapy in Belgium. Methods and results This prospective registry includes 41 consecutive patients treated with the Mitraclip® in two Belgian centres from October 2010 to June 2013. Acute procedural success, in-hospital safety end points and clinical status were analysed on an intention-to-treat basis up to one year after the procedure. In addition, determinants of major adverse cardiac events (MACE, death, surgical mitral valve intervention, and rehospitalization for heart failure) were analysed. Acute procedural success (successful clip placement and reduction of colour Doppler flow MR to ≤ 2) was obtained in 32 patients (78%) and 18 of these patients received two clips. The primary safety end point was reached in 36 pts (88%): one patient died due to intracranial bleeding, there were three urgent surgical interventions and one severe access site bleeding. The MACE rate after one year was 41% (17 patients). There were 11 deaths (27%), six surgical interventions (15%) and 10 rehospitalizations for heart failure (24%). Additional subgroup analysis revealed that the one-year MACE rate was particularly high in patients with left ventricular ejection fraction (LVEF) < 25%: 62% vs. 36% in patients with LVEF ≥ 25% (P = 0.05). At one year, MR ≤ 2+ and NYHA class ≤ 2 was present in 83% of the surviving patients Conclusion In high-risk patients with functional MR, treatment with the Mitraclip®-device is a feasible and safe option resulting in improvement of MR severity and clinical symptoms. However, as MACE is high in some subgroups (e.g. LVEF < 25%), careful patient selection is crucial to ensure the maximum benefit from this new technique.

Prognostic Implications of Magnetic Resonance–Derived Quantification in Asymptomatic Patients With Organic Mitral Regurgitation: Comparison With Doppler Echocardiography–Derived Integrative Approach

Background: Magnetic resonance imaging (MRI) is an accurate method for the quantitative assessment of organic mitral regurgitation (OMR). The aim of the present study was to compare the discriminative power of MRI quantification and the recommended Doppler echocardiography (ECHO)–derived integrative approach to identify asymptomatic patients with OMR and adverse outcome. Methods: The study population consisted of 258 asymptomatic patients (63±14 years, 60% men) with preserved left ventricular ejection fraction (>60%) and chronic moderate and severe OMR (flail 25%, prolapse 75%) defined by using the ECHO-derived integrative approach. All patients underwent MRI to quantify regurgitant volume (RV) of OMR by subtracting the aortic forward flow volume from the total left ventricular stroke volume. Severe OMR was defined as RV≥60 mL. Results: Mean ECHO-derived RV was on average 17.1 mL larger than the MRI-derived RV (P<0.05). Concordant grading of OMR severity with both techniques was observed in 197 (76%) individuals with 62 (31%) patients having severe OMR (MRI SEV-ECHO SEV) and 135 (69%) patients having moderate OMR (MRI MOD-ECHO MOD). The remaining 61 (24%) individuals had discordant findings (MRI SEV-ECHO MOD or MRI MOD-ECHO SEV) between the 2 techniques. The majority of these differences in OMR classification were observed in patients with late systolic or multiple jets (both &kgr;<0.2). Patients with eccentric jets showed moderate agreement (&kgr;=0.53; 95% confidence interval, 0.41–0.64). In contrast, a very good agreement (&kgr;=0.90; 95% confidence interval, 0.82–0.98) was observed in a combination of holosystolic, central, and single jet. During a median follow-up of 5.0 years (interquartile range, 3.5–6.0 years), 38 (15%) patients died and 106 (41%) either died or developed indication for mitral valve surgery. In separate Cox regression analyses, the MRI-derived left ventricular end-systolic volume index, RV, and OMR category (severe versus moderate), and the ECHO-derived OMR category were independent predictors of all-cause mortality (all P<0.05). The MRI-derived RV showed the largest area under the curve to predict mortality (0.72) or its combination with the development of indication for mitral valve surgery (0.83). Conclusions: The findings of the present study suggest that the MRI-derived assessment of OMR can better identify patients with severe OMR and adverse outcome than ECHO-derived integrative approach warranting close follow-up and perhaps, early mitral valve surgery.

Echocardiographic reference ranges for normal left atrial function parameters: results from the EACVI NORRE study

Aims To obtain the normal ranges for echocardiographic measurements of left atrial (LA) function from a large group of healthy volunteers accounting for age and gender. Methods and results A total of 371 (median age 45 years) healthy subjects were enrolled at 22 collaborating institutions collaborating in the Normal Reference Ranges for Echocardiography (NORRE) study of the European Association of Cardiovascular Imaging (EACVI). Left atrial data sets were analysed with a vendor-independent software (VIS) package allowing homogeneous measurements irrespective of the echocardiographic equipment used to acquire data sets. The lowest expected values of LA function were 26.1%, 48.7%, and 41.4% for left atrial strain (LAS), 2D left atrial emptying fraction (LAEF), and 3D LAEF (reservoir function); 7.7%, 24.2%, and -0.53/s for LAS-active, LAEF-active, and LA strain rate during LA contraction (SRa) (pump function) and 12.0% and 21.6% for LAS-passive and LAEF-passive (conduit function). Left atrial reservoir and conduit function were decreased with age while pump function was increased. All indices of reservoir function and all LA strains had no difference in both gender and vendor. However, inter-vendor differences were observed in LA SRa despite the use of VIS. Conclusion The NORRE study provides contemporary, applicable echocardiographic reference ranges for LA function. Our data highlight the importance of age-specific reference values for LA functions.

Assessment of mechanical dyssynchrony can improve the prognostic value of guideline-based patient selection for cardiac resynchronization therapy

Aim To determine if incorporation of assessment of mechanical dyssynchrony could improve the prognostic value of patient selection based on current guidelines. Methods and results Echocardiography was performed in 1060 patients before and 12 ± 6 months after cardiac resynchronization therapy (CRT) implantation. Mechanical dyssynchrony, defined as the presence of apical rocking or septal flash was visually assessed at the baseline examination. Response was defined as ≥15% reduction in left ventricular end-systolic volume at follow-up. Patients were followed for a median of 59 months (interquartile range 37-86 months) for the occurrence of death of any cause. Applying the latest European guidelines retrospectively, 63.4% of the patients had been implanted with a Class I recommendation, 18.2% with Class IIa, 9.4% with Class IIb, and in 9% no clear therapy recommendation was present. Response rates were 65% in Class I, 50% in IIa, 38% in IIb patients, and 40% in patients without a clear guideline-based recommendation. Assessment of mechanical dyssynchrony improved response rates to 77% in Class I, 75% in IIa, 62% in IIb, and 69% in patients without a guideline-based recommendation. Non-significant difference in survival among guideline recommendation classes was found (Log-rank P = 0.2). Presence of mechanical dyssynchrony predicted long-term outcome better than guideline Classes I, IIa, IIb (Log-rank P < 0.0001, 0.006, 0.004, respectively) and in patients with no guideline recommendation (P = 0.02). Comparable results were observed using the latest American Guidelines. Conclusion Our data suggest that current guideline criteria for CRT candidate selection could be improved by incorporating assessment of mechanical asynchrony.