Left Ventricular Response Research Articles

Left ventricular end-diastolic pressure response to spinal anaesthesia in euvolaemic vascular surgery patients

Left ventricular end-diastolic pressure response to spinal anaesthesia in euvolaemic vascular surgery patients

Association between echocardiography-derived haemodynamic force parameters and left ventricular reverse remodelling after cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) may induce left ventricular (LV) reverse remodelling (=LV response) in patients with heart failure. Intraventricular pressure gradients can be quantified using echocardiography-derived haemodynamic forces (HDF). The aim was to evaluate the association between baseline HDF and LV response and to compare the change of HDF after CRT between LV responders and LV non-responders. The following HDF parameters were assessed: 1)apical-basal (AB) strength, 2)lateral-septal strength, 3)force vector angle, 4)systolic AB impulse, 5)systolic force vector angle. LV response was defined as a reduction of LV end-systolic volume ≥15% at six months. One hundred ninety-six patients were included (64±11 years, 122(62%) men), 136(69%) showed LV response. On multivariable logistic regression analysis, the force vector angle in the complete heart cycle (OR 1.083 (95%CI 1.018, 1.153), p=0.012) and the systolic force vector angle (OR 1.089 (95%CI 1.021, 1.161), p=0.009), both included in separate models, were independently associated with LV response. Six months after CRT, LV responders had greater AB strength, AB impulse and higher force vector angles, while LV non-responders only showed improvement in the force vector angle in the complete heart cycle. The orientation of HDF at baseline is associated with LV response to CRT. Six months after CRT, the orientation of HDF improves in LV responders and LV non-responders, while the magnitude of AB HDF only improves in LV responders.

Unraveling the Enigma of Moderate Aortic Stenosis: Challenges and Future Prospects.

According to current guidelines, only clinical surveillance is recommended for patients with moderate aortic valve stenosis (AS), while aortic valve replacement may be considered in patients undergoing surgery for other indications. Recent studies have shown that moderate AS is associated with a high risk of adverse cardiovascular events, including death, especially in patients with left ventricular dysfunction. In this context, multimodality imaging can help to improve the accuracy of moderate AS diagnosis and to assess left ventricular remodeling response. This review discusses the natural history of this valve disease and the role of multimodality imaging in the diagnostic process, summarizes current evidence on the medical and non-medical management, and highlights ongoing trials on valve replacement.

Leadless ultrasound-based cardiac resynchronization system in heart failure results from the SOLVE-CRT randomised sub-study and the primary population patient cohort

Abstract Background Despite the well-established role of CRT in heart failure, major limitations of CRT include an occasional incidence of unsuccessful coronary sinus (CS) lead placement, one third non-responders in conventional CRT patients and higher complications risk in CRT upgrade procedures. The WiSE® CRT System (EBR Systems, Inc) is designed to overcome these limitations. Prior non-randomized studies with the WiSE System have shown high implant success rates and improvement in LV remodeling and heart failure symptoms. Objectives The pivotal SOLVE-CRT study is comprised of two parts: a randomized part and the subsequent single-arm part enrolled during the pandemic. The primary safety endpoint is freedom from Type I (device & procedure-related) complications through 6 months and primary efficacy endpoint is the mean relative (%) change in left ventricular end systolic volume (LVESV) from baseline to 6 months. Method Between Jan. 2018 and Mar. 2020 the randomized part enrolled 108 participants for three indications: non-responders (NR), previously untreated, including acute and chronic lead failures (PU), and high-risk upgrades (HRU). All underwent device implantation and were then randomized in 1:1 ratio to Treatment (system turned ON) or Control (system turned OFF) groups. In the single arm, 75 participants had been enrolled within two indications: PU and HRU. The efficacy analysis of the entire randomised cohort included 99 participants (PU, HRU, NR). For the primary indication sub-population, 57 participants (PU, HRU) were analysed. Results Randomized Group: Results were available for 91 of the 99 patients. Significant improvements were seen between the Treatment and Control groups with a mean reduction in LVESV (-14.6% vs -5.2%, p=0.005), mean reduction in LVEDV (-8.1% vs -3.0%, p=0.027), mean increase in LVEF (5.4% vs 2.4%, p=0.048) and mean reduction in QRS (-41.9ms vs -1.7ms, p=0.001). Primary Indication Sub-Population Group: The primary indication sub-population also saw significant improvements between Treatment and Control group with a mean reduction in LVESV (-18.2% vs -3.1%, p=0.002), mean reduction in LVEDV (-11.6% vs -2.1%, p=0.004), mean increase in LVEF (5.7% vs 1.1%, p=0.025) and mean reduction in QRS (-38.0ms vs -3.1ms, p<0.001). Conclusion This pivotal SOLVE-CRT trial demonstrates that leadless, ultrasound-based endocardial pacing for heart failure is feasible and efficacious showing evidence of left ventricular remodelling and electrical response after 6 month in the primary population as well as in the sub-study group. Picture 1: Efficacy entire randomised population Picture 2: Efficacy primary indications population

Sex Differences in Left Ventricular Stroke Volume During Muscle Metaboreflex Activation

Introduction: Muscle metaboreflex activation (MMA) increases blood pressure, possibly by disproportionate increases in left ventricular (LV) stroke volume (SV) in males compared to females due to greater grip strength and metabolite production. The purpose of this study was to determine the effect of sex on SV during isolated MMA using cardiac MRI in young healthy adults. We hypothesized that SV would increase during MMA to a greater degree in males compared to females, and that this effect would be negated by accounting for grip strength. Methods: Ten males [23(2) yrs] and 10 females [26(5) yrs] underwent cardiac MRI during rest, 30% maximal voluntary contraction (MVC) isometric handgrip exercise (6 min), and isolation of MMA with brachial cuff circulatory occlusion (6 min). SV, end-systolic (ESV) and end-diastolic volumes (EDV) were measured by 2- and 4-chamber cine images and indexed (i) to body surface area to account for body size. Heart rate (HR, ECG) and mean arterial pressure (MAP, brachial cuff) were recorded. Cardiac output index (COi) and total peripheral resistance (TPR) were calculated. Analyses included ANOVA (sex × condition), ANCOVA [100% MVC (M=49(13) kg, F=26(7) kg) covariate], and linear regression. Results: SVi decreased from rest to MMA in males [67(8) to 61(5) mL/m2, p=0.0001] but not females [59(9) to 59(7) mL/m2, p=0.998; interaction p=0.002]. Notably, the reduction in SVi during MMA in males ( p=0.002) but not females ( p=0.957) remained with ANCOVA using MVC as the covariate (interaction p=0.021). ESVi increased during MMA in males [39(5) to 48(10) mL/m2, p<0.0001] but not females [32(5) to 36(6) mL/m2, p=0.092; interaction p=0.029]. MMA decreased both EDVi ( p=0.004) and COi ( p=0.045) and increased both MAP ( p<0.0001) and TPR ( p<0.0001) pooled across sex. HR did not change with MMA in either sex (all p≥0.093). Linear regression revealed significant relationships between ΔSVi and ΔESVi in males ( p=0.002, R2=0.709) but not females ( p=0.223, R2=0.179) and between ΔSVi and ΔTPR in males ( p=0.005, R2=0.649) but not females ( p=0.522, R2=0.053). Conclusions: MMA lowers SVi in males but not females, even when accounting for grip strength and despite similar pressor responses in both groups. These findings from gold-standard MRI suggest differential LV responses to MMA between sexes, potentially related to greater sensitivity to increased TPR in males than females. Thus, sex differences in blood pressure control during MMA may be impacted by differences in LV afterload sensitivity. Further, the blood pressure response to MMA may be primarily mediated through TPR and not CO in healthy young adults. Heart and Stroke Foundation of Canada. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Cardiac magnetic resonance patterns of left ventricular remodeling in patients with severe aortic stenosis referred to surgical aortic valve replacement

Left ventricular (LV) hypertrophy is a common finding in patients with severe aortic stenosis (AS). Cardiac magnetic resonance (CMR) is the gold-standard technique to evaluate LV remodeling. Our aim was to assess the prevalence and describe the patterns of LV adaptation in AS patients before and after surgical aortic valve replacement (AVR). Prospective study of 130 consecutive patients (71y [IQR 68–77y], 48% men) with severe AS, referred for surgical AVR. Patterns of LV remodeling were assessed by CMR. Besides normal LV ventricular structure, four other patterns were considered: concentric remodeling, concentric hypertrophy, eccentric hypertrophy, and adverse remodeling. At baseline CMR study: mean LV indexed mass: 81.8 ± 26.7 g/m2; mean end-diastolic LV indexed volume: 85.7 ± 23.1 mL/m2 and median geometric remodeling ratio: 0.96 g/mL [IQR 0.82–1.08 g/mL]. LV hypertrophy occurred in 49% of subjects (concentric 44%; eccentric 5%). Both normal LV structure and concentric remodeling had a prevalence of 25% among the cohort; one patient had an adverse remodeling pattern. Asymmetric LV wall thickening was present in 55% of the patients, with predominant septal involvement. AVR was performed in 119 patients. At 3–6 months after AVR, LV remodeling changed to: normal ventricular geometry in 60%, concentric remodeling in 27%, concentric hypertrophy in 10%, eccentric hypertrophy in 3% and adverse remodeling (one patient). Indexes of AS severity, LV systolic and diastolic function and NT-proBNP were significantly different among the distinct patterns of remodeling. Several distinct patterns of LV remodelling beyond concentric hypertrophy occur in patients with classical severe AS. Asymmetric hypertrophy is a common finding and LV response after AVR is diverse.

High-Intensity Interval Training Is Associated With Improved 10-Year Survival by Mediating Left Ventricular Remodeling in Patients With Heart Failure With Reduced and Mid-Range Ejection Fraction.

This study aimed to assess the left ventricular (LV) remodeling response and long-term survival after high-intensity interval training (HIIT) in patients with various heart failure (HF) phenotypes during a 10-year longitudinal follow-up. Among 214 patients with HF receiving guideline-directed medical therapy, those who underwent an additional 36 sessions of aerobic exercise at alternating intensities of 80% and 40% peak oxygen consumption (O2peak) were considered HIIT participants (n=96). Patients who did not undergo HIIT were considered participants receiving guideline-directed medical therapy (n=118). Participants with LV ejection fraction (EF) <40%, ≥40% and <50%, and ≥50% were considered to have HF with reduced EF, HF with mid-range EF, and HF with preserved EF, respectively. O2peak, serial LV geometry, and time to death were recorded. In all included participants, 10-year survival was better (P=0.015) for participants who underwent HIIT (80.3%) than for participants receiving guideline-directed medical therapy (68.6%). An increased O2peak, decreased minute ventilation carbon dioxide production slope, and reduced LV end-diastolic diameter were protective factors against all-cause mortality. Regarding 138 patients with HF with reduced EF (P=0.044) and 36 patients with HF with mid-range EF (P=0.036), 10-year survival was better for participants who underwent HIIT than for participants on guideline-directed medical therapy. Causal mediation analysis showed a significant mediation path for LV end-diastolic diameter on the association between HIIT and 10-year mortality in all included patients with HF (P<0.001) and those with LV ejection fraction <50% (P=0.006). HIIT also had a significant direct association with 10-year mortality in patients with HF with LV ejection fraction <50% (P=0.027) but not in those with LV ejection fraction ≥50% (n=40). Reversal of LV remodeling after HIIT could be a significant mediating factor for 10-year survival in patients with HF with reduced EF and those with HF with mid-range EF.

Left ventricular remodeling in twin pregnancy, noninvasively assessed using hemodynamic forces and pressure-volume relation analysis: prospective, cohort study.

This study was designed to prospectively investigate the pattern of intraventricular hemodynamic forces (HDFs) associated with left ventricular (LV) function and remodeling in women with uncomplicated twin pregnancy. Transthoracic echocardiography was performed on 35 women (aged 35.9 ± 4.7-yr old) during gestation (T1, <14 wk; T2, 14-27 wk; T3, >28 wk) and 6-7 mo after delivery (T0). LV HDFs were computed from echocardiography long-axis data sets using a novel technique based on endocardial boundary tracking, both in apex-base (A-B) and latero-septal (L-S) directions. HDF distribution was evaluated by L-S over A-B HDF ratio (L-S:A-B HDF ratio). At T1, L-S:A-B HDF ratio was higher than in T0 (P < 0.05) indicating HDF misalignment. At T2, a slight impairment of cardiac function was then recorded with a reduction of global longitudinal strain (GLS) and left ventricular end-systolic elastance (Ees) at pressure-volume relationship analysis versus T1 (both P < 0.05). Finally, at T3, when HDF misalignment and LV contractility reduction (GLS and Ees) were all restored, a rightward shift of the end-diastolic pressure-volume relationship (EDPVR) with an increase of ventricular capacitance was documented. In twin pregnancy, HDF misalignment in the first trimester precedes the slight temporary decrease in left ventricular systolic function in the second trimester; at the third trimester, a rightward shift of the EDPVR was associated with a realignment of HDF and normalization of ventricular contractility indexes. These coordinated changes that occur in the maternal heart during twin pregnancy suggest the role of HDFs in cardiac remodeling.NEW & NOTEWORTHY These changes indicate that 1) the misalignment of hemodynamic forces (HDFs) precedes a mild reduction in systolic function in twin pregnancy and 2) the positive left ventricular (LV) response to hemodynamic stress is mainly due to an improved diastolic function with enhanced LV cavity compliance.

Patients with volume-loaded right ventricle - quantification of left ventricular hemodynamic response to intervention measured by noninvasive pressure-volume loops.

Volume loading of the right ventricle (RV) in patients with atrial septal defect (ASD) and patients with repaired Tetralogy of Fallot (rToF) affects the pumping mechanics of the left ventricle (LV). Intervention of the lesion will relieve the RV volume load however quantifiable impact on exercise capacity, arrhytmias or death are limited. A possible explanation could be remaining effects on the function of the LV. The aim of this study was therefore to investigate if hemodynamics of the LV differs between patients with RV volume load due to ASD or rToF and healthy controls and if they change after intervention. Eighteen patients with ASD, 17 patients with rToF and 16 healthy controls underwent cardiac magnetic resonance imaging (CMR) and maximal exercise test with continuous gas analysis. Reexamination was performed 13 ± 2months after closure of the ASD in 13 of the patients and 10 ± 4months after pulmonary valve replacement (PVR) in 9 of the patients with rToF. Non-invasive PV-loops from CMR and brachial pressures were analyzed. Stroke work (SW) and potential energy (PE) increased after ASD closure but not in ToF patients after valve repair. Patients with ASD or rToF had higher contractility and arterial elastance than controls. No major effects were seen in LV energetics or in peak VO2 after ASD closure or PVR. Peak VO2 correlated positively with SW and PE in patients with ASD (r = 0.54, p < 0.05; r = 0.61, p < 0.01) and controls (r = 0.72, p < 0.01; r = 0.53, p < 0.05) to approximately the same degree as peak VO2 and end-diastolic volume (EDV) or end-systolic volume (ESV). In ToF patients there was no correlation between PV loop parameters and peak VO2 even if correlation was found between peak VO2 and EDV or ESV. In conclusion, the LV seems to adapt its pumping according to anatomic circumstances without losing efficiency, however there are indications of persistent vascular dysfunction, expressed as high arterial elastance, which might have impact on exercise performance and prognosis. Future studies might elucidate if the duration of RV volume load and decreased LV filling have any impact on the ability of the vascular function to normalize after ASD closure or PVR.

Left and right ventricular hemodynamic response after transcatheter mitral valve replacement

Abstract Background Transcatheter mitral valve replacement (TMVR) represents a novel treatment option for patients with relevant mitral regurgitation (MR), who are ineligible for surgical treatment. Although complete and predictable elimination of MR is achieved in most patients undergoing TMVR, little is known about left and right ventricular hemodynamic changes after TMVR. Purpose With this study, we sought to investigate left ventricular (LV) remodeling and right ventricular (RV) function in patients undergoing TMVR using data derived from non-invasive, echocardiography-based pressure volume loops. Methods A total of 49 consecutive patients with MR 3+ or 4+ undergoing TMVR with one of four dedicated devices were included in a prospective single-center TMVR registry between 05/2016 until 08/2022. For this study, only patients with technical success and available echocardiographic data at baseline and discharge were included. The end-diastolic and end-systolic pressure-volume relationships (EDPVR and ESPVR) were estimated non-invasively using single-beat echocardiographic measurements. VPed20 was calculated as a parameter describing the end-diastolic volume (EDV) at an end-diastolic pressure (EDP) of 20 mmHg. Ees, the slope describing the ESPVR, was calculated as surrogate parameter for LV contractility. Pulmonary artery systolic pressure (PASP), tricuspid annular plane systolic excursion (TAPSE) and RV-pulmonary artery (PA) coupling were assessed as parameters reflecting RV function. Results A total of 26 patients (77.0 years [IQR 73.9-80.1], N=17 [65.4%] male) with successful TMVR were included (secondary MR [N=21, 80.8%]; median LV ejection fraction 37.0% [IQR 30.7-50.7]). Overall, a significant decrease in VPed20 was observed following TMVR indicating a leftward shift of the EDPVR (165.3±75.8mL vs. 134.0±65.9mL, p&amp;lt;0.001, Figure 1). In addition, Ees increased from 1.4±0.9 at baseline to 2.5±2.4 at discharge (p=0.0071) indicating an increaseed intrinsic LV contractility, while LV ejection fraction remained unchanged, but forward ejection fraction improved significantly (38.9±21.9% vs. 53.4±29.8%, p&amp;lt;0.001) (Figure 1). After the procedure we observed an increased left-ventricular end-diastolic pressure (LVEDP) (22.6±4.0mmHg vs. 26.1±5.1mmHg, p=0.012). However, PASP significantly decreased (50.5±16.5mmHg vs. 35.7±10.8mmHg, p&amp;lt;0.001). While TAPSE (18.1±5.5mm vs. 15.5±5.8mm, p=0.015) was also decreased at discharge, RV-PA coupling remained stable (0.4±0.2mm/mmHg vs. 0.5±0.2mmHg, p=0.19). Conclusions Non-invasive assessment of pressure volume loops before and after TMVR demonstrate an early LV reverse remodelling effect and improved systolic LV contractility, while RV performance was preserved. These results indicate the potential impact of complete MR elimination after TMVR on LV and RV function. Long-term data are needed to assess the prognostic impact of MR elimination and LV reverse remodelling following TMVR.Figure 1

Left ventricular remodeling response to SGLT2 inhibitors in heart failure: an updated meta-analysis of randomized controlled studies

BackgroundRandomized controlled trials (RCTs) reported contrasting results about reverse left ventricular remodeling (LVR) after sodium-glucose co-transporter-2 inhibitors (SGLT2i) therapy in patients with heart failure (HF).Methods and resultsWe performed a metanalysis of RCTs of SGLT2i administration in HF outpatients published until June 2022 searching four electronic databases. The protocol has been published in PROSPERO. Primary LVR outcome was change in absolute LV end-diastolic (LVEDV) and end-systolic volume (LVESV) from baseline to study endpoint. Secondary outcomes included changes in LVEDV and LVESV indexed to body surface area, LV Mass index (LVMi), LV ejection fraction (LVEF), and N-terminal pro-B-type natriuretic peptide (NTproBNP). Mean differences (MDs) with 95% CIs were pooled. A total of 9 RCTs (1385 patients) were analyzed. All of them reported data on LVEF. Six trials reported data on LVESV and LVEDV (n = 951); LVMi was available in 640. SGLT2i treatment significantly reduced LVEDV [MD= -10.59 ml (-17.27; -3.91), P = 0.0019], LVESV [MD= -8.80 ml (-16.91; -0.694), P = 0.0334], and LVMI [MD= -5.34 gr/m2 (-9.76; -0.922), P = 0.0178], while LVEF significantly increased [MD = + 1.98% (0.67; 0.306), P = 0.0031]. By subgroup analysis, the beneficial effects of SGLT2i on LVEF did not differ by imaging method used, time to follow-up re-evaluation, or HF phenotype. Reduction in LV volumes tended to be greater in HF with reduced EF (HFrEF) than in those with preserved EF (HFpEF), while the opposite was observed for LVMi.ConclusionsTreatment with SGLT2i significantly reversed cardiac volumes, improving LV systolic function and LV mass, particularly in HFrEF patients.

Muscle metaboreflex control of left ventricular systolic function in heart failure with reduced ejection fraction.

Heart failure with reduced ejection fraction (HFrEF) exhibits exaggerated sympathoexcitation and altered cardiac and vascular responses to muscle metaboreflex activation (MMA). However, left ventricular (LV) responses to MMA are not well studied in patients with HFrEF. The purpose of this study was to examine LV function during MMA using cardiac magnetic resonance imaging (MRI) in patients with HFrEF. Thirteen patients with HFrEF and 18 healthy age-matched controls underwent cardiac MRI during rest and MMA. MMA protocol included 6 min of isometric handgrip exercise followed by 6-min of brachial postexercise circulatory occlusion. LV stroke volume index (SVi), end-systolic volume index (ESVi), end-diastolic volume index (EDVi), and global longitudinal strain (GLS) were measured by two- and four-chamber cine images. Volumes were indexed to body surface area. Heart rate (via ECG) and brachial mean arterial pressure (MAP) were recorded. Cardiac output and total peripheral resistance (TPR) were calculated. SVi decreased during MMA in HFrEF (P = 0.037) but not in controls (P = 0.392). ESVi (P = 0.007) and heart rate (P < 0.001) increased during MMA in HFrEF but not controls (P ≥ 0.170). TPR (P = 0.021) and MAP (P < 0.001) increased during MMA in both groups. Cardiac output (P = 0.946), EDVi (P = 0.177), and GLS (P = 0.619) were maintained from rest to MMA in both groups. Despite similarly maintained cardiac output, LV strain, and increased TPR in HFrEF and control groups, SVi decreased, and heart rate increased during MMA in patients with HFrEF. These findings suggest an impaired contractility reserve in response to increased TPR during MMA in HFrEF.NEW & NOTEWORTHY Stroke volume decreases and end-systolic volume increases during muscle metaboreflex activation in patients with heart failure with reduced ejection fraction (HFrEF), suggesting impaired contractile reserve during muscle metaboreflex activation in patients with HFrEF. Total peripheral resistance increases similarly during muscle metaboreflex activation in patients with HFrEF compared to controls, indicating normal levels of peripheral vasoconstriction during muscle metaboreflex activation in patients with HFrEF.

Left ventricular response to short exercise in long term non-hodgkin lymphoma survivors

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Echocardiographic left ventricular (LV) global longitudinal strain (GLS) may be used to detect subclinical ventricular dysfunction in patients who have received cardiotoxic chemotherapy. However, in some persons participating in recreational sports, GLS at rest may be lower than normal, but normalizes after a short exercise test as soon as resting heart rate (HR) is reached. The aim of the study was to determine GLS response to a short exercise test in patients treated for aggressive non- Hodgkin Lymphoma (NHL) compared to controls. Methods We conducted a cross-sectional study nested in a cohort of NHL survivors and their siblings served as controls . Survivors were treated 5 years ago or longer with a cumulative doxorubicin (anthracycline) dose of at least 250 mg/m2. Transthoracic Echocardiography (TTE) was performed according to the guidelines. First, GLS and LV ejection fraction (EF) were measured at rest. After 20 squats, GLS and EF measurements were repeated when the HR was comparable to the HR during rest measurements. Results In total 20 survivors (mean age 49 (± 13) years, 11 men (55%) were included and measurements were compared to 14 controls. (mean age 45 (± 8) years, 8 men ( 57 %). In patients at rest, the EF was 52.6% ( ± 8.0%) and the GLS −16.1% ( ± 2.9%), compared to controls with an EF of 56.2% (± 3.4% ) (p-value 0.13) and GLS −18.0% (± 1.4 %) (p-value 0.031). All patients performed 20 squats and their EF increased to 55.0% (± 6.8%) and GLS −18.7% (± 3.8%) compared to controls in whom the EF increased to 62% (± 4.7%) (p-value 0.002) and GLS −21.3% (± 2.5%) (p-value 0.037) (Figure 1). Conclusion In addition to GLS measurement at rest, GLS after a short exercise test seems to be a promising tool to detect subclinical LV dysfunction in non-Hodgkin Lymphoma survivors. Further research in larger studies is needed to confirm these findings and to assess the association with clinical parameters.

Late left ventricular myocardial remodeling after pulmonary artery banding for end-stage dilated cardiomyopathy in infants: an imaging study

BackgroundUnderstanding the macroscopic biventricular changes induced by pulmonary artery banding (PAB) in children with dilated cardiomyopathy (DCM) represents the first step to unraveling the regenerative potential of the myocardium. We herein investigated the phases of left ventricular (LV) rehabilitation in PAB responders, using a systematic echocardiographic and cardiac magnetic imaging (CMRI) surveillance protocol. MethodsWe prospectively enrolled all patients with DCM treated with PAB from September-2015 at our institution. Among 9 patients, 7 positively responded to PAB and were selected. Transthoracic 2D echocardiography was performed before PAB; and 30, 60, 90, and 120 days after PAB; and at the last available follow-up. CMRI was performed before PAB (whenever possible) and one year after PAB. ResultsIn PAB responders, LV ejection fraction showed a modest 10% increase 30–60 days after PAB, followed by its almost complete normalization after 120 days (median of 20[10–26]% vs 56[44.5–63.5]%, at baseline and 120 days after PAB, respectively). Parallelly, the LV end-diastolic volume decreased from a median of 146(87–204)ml/m2 to 48(40–50)ml/m2. At the last available follow-up (median of 1.5 years from PAB), both echocardiography and CMRI showed a sustained positive LV response, although myocardial fibrosis was detected in all patients. ConclusionsEchocardiography and CMRI show that PAB can promote a LV remodeling process, which starts slowly and can culminate in the normalization of LV contractility and dimensions 4 months later. These results are maintained up to 1.5 years. However, CMRI showed residual fibrosis as evidence of a past inflammatory injury whose prognostic significance is still uncertain.

Acute and Chronic Changes in Myocardial Work Parameters in Patients with Severe Primary Mitral Regurgitation Undergoing Transcatheter Edge-to-Edge Repair.

The noninvasive assessment of myocardial work (MW) allows for the evaluation of left ventricular (LV) performance by considering the effect of LV afterload. This study aims to evaluate the acute and chronic impact of transcatheter edge-to-edge repair (TEER) on MW parameters and LV remodeling in patients with severe primary mitral regurgitation (PMR). A total of 71 patients (age: 77 ± 9 years, females: 44%) with moderate-to-severe or severe PMR (effective regurgitant orifice: 0.57 ± 0.31 cm2; regurgitant volume: 80 ± 34 mL; LV end-systolic diameter: 42 ± 12 mm) underwent TEER after a global assessment by the heart team. MW indices were evaluated before the procedure, at hospital discharge, and at 1-year follow-up. LV remodeling was described as the percentage variation in LVEDV between baseline and 1-year follow-up. TEER caused an acute reduction in LVEF, global longitudinal strain (GLS), global MW index (GWI), work efficiency (GWE), and mechanical dispersion (MD) and a significant increase in wasted work (GWW). One year after the procedure, GLS, GWI, GWE, and MD recovered, whereas GWW remained significantly impaired. Baseline GWW (β = -0.29, p = 0.03) was an independent predictor of LV reverse remodeling at 1-year follow-up. In patients with severe PMR undergoing TEER, the acute reduction in LV preload causes significant impairment to all the parameters of LV performance. Baseline GWW was the only independent predictor of LV reverse remodeling, suggesting that a lower myocardial energetic efficiency in the context of chronic preload increase might impact the left ventricular response to mitral regurgitation correction.

Severe sleep apnea as a predictor of failure to respond to cardiac resynchronization therapy

BackgroundThe response to cardiac resynchronization therapy (CRT) is suboptimal in one-third of patients. ObjectivesThe study aimed to evaluate the impact of sleep-disordered breathing (SDB) on the CRT-induced left ventricular (LV) reverse remodeling and response for CRT in patients with ischemic congestive heart failure (CHF). MethodsA total of 37 patients aged 65.43 years (SD 6.05), seven of whom were females, were treated with CRT according to class I European Society of Cardiology recommendations. Clinical evaluation, polysomnography, and contrast echocardiography were performed twice during the six-month follow-up (6M-FU) to assess the effect of CRT. ResultsIn 33 patients (89.1%), sleep-disordered breathing (SDB), predominantly central sleep apnea (70.3%) was observed. This include nine patients (24.3%) with an apnea-hypopnea index (AHI) of >30 events/hour. During the 6M-FU, 16 patients (47.1%) responded to CRT by reducing LV end-systolic volume index (LVESVi) by ≥15%. We stated a directly proportional linear relationship between AHI value and LV volume: LVESVi p = 0.004, and LV end-diastolic volume index p = 0.006. ConclusionsPre-existing severe SDB can impair the LV volumetric response to CRT even in an optimally selected group with class I indications for resynchronization, which may have an impact on long-term prognosis.

Myocardial inefficiency is an early indicator of exercise-induced myocardial fatigue.

The effect of prolonged, high-intensity endurance exercise on myocardial function is unclear. This study aimed to determine the left ventricular (LV) response to increased exercise duration and intensity using novel echocardiographic tools to assess myocardial work and fatigue. LV function was assessed by echocardiography before, immediately, and 24 h after a cardiopulmonary exercise test (CPET) and a 91-km mountain bike leisure race. Cardiac Troponin I (cTnI) was used to assess myocyte stress. 59 healthy recreational athletes, 52 (43-59) years of age, 73% males, were included. The race was longer and of higher intensity generating higher cTnI levels compared with the CPET (p < 0.0001): Race/CPET: exercise duration: 230 (210, 245)/43 (40, 45) minutes, mean heart rate: 154 ± 10/132 ± 12 bpm, max cTnI: 77 (37, 128)/12 (7, 23) ng/L. Stroke volume and cardiac output were higher after the race than CPET (p < 0.005). The two exercises did not differ in post-exercise changes in LV ejection fraction (LVEF) or global longitudinal strain (GLS). There was an increase in global wasted work (p = 0.001) following the race and a persistent reduction in global constructive work 24 h after exercise (p = 0.003). Increased exercise intensity and duration were associated with increased myocardial wasted work post-exercise, without alterations in LVEF and GLS from baseline values. These findings suggest that markers of myocardial inefficiency may precede reduction in global LV function as markers of myocardial fatigue.

Multimodality Imaging to Explore Sex Differences in Aortic Stenosis.

The aim of this article is to review sex differences in aortic stenosis (AS) assessed with multimodality imaging. Echocardiography remains the mainstay imaging technique to diagnose AS and provides important insights into the differences between men and women in relation to valve haemodynamic and left-ventricular response. However, echocardiography does not have adequate resolution to provide important insights into sex differences in the degenerative, calcific pathophysiological process of the aortic valve. CT shows that women with AS have more fibrotic changes of the aortic valve whereas men show more calcific deposits. Cardiac magnetic resonance shows that women have left ventricles that are less hypertrophic and smaller compared with those of men, while men have more replacement myocardial fibrosis. These differences may lead to different responses to aortic valve replacement because myocardial diffuse fibrosis but not replacement myocardial fibrosis may regress after the procedure. Sex differences in the pathophysiological process of AS can be assessed using multimodality imaging, assisting in decisionmaking in these patients.

Left Ventricular Responses during Exercise in Highly Trained Youth Athletes: Echocardiographic Insights on Function and Adaptation.

There is an increase in the prevalence of elite youth sports academies, whose sole aim is to develop future elite athletes. This involves the exposure of the child and adolescent athlete to high-volume training during a period of volatile growth. The large amount of data in this area has been garnered from the resting echocardiographic left ventricular (LV) evaluation of the youth athlete; while this can provide some insight on the functional adaptations to training, it is unable to elucidate a comprehensive overview of the function of the youth athletes' LV during exercise. Consequently, there is a need to interrogate the LV responses in-exercise. This review outlines the feasibility and functional insight of capturing global indices of LV function (Stroke Index-SVIndex and Cardiac Index-QIndex), systolic and diastolic markers, and cardiac strain during submaximal and maximal exercise. Larger SVI and QI were noted in these highly trained young athletes compared to recreationally active peers during submaximal and maximal exercise. The mechanistic insights suggest that there are minimal functional systolic adaptions during exercise compared to their recreationally active peers. Diastolic function was superior during exercise in these young athletes, and this appears to be underpinned by enhanced determinants of pre-load.

Left Ventricular Diastolic Response to Isometric Handgrip Exercise in Physically Active and Sedentary Individuals.

This study aims to investigate the diastolic left ventricular (LV) response to isometric handgrip exercise among healthy middle-aged men with high physical activity levels, versus matched sedentary individuals. Two groups of 10 men aged 41-51 years were studied. Men in the first group had high weekly self-reported physical activity levels (&gt;3000 METs × min/week). In comparison, men in the second group reported low physical activity levels (&lt;300 METs × min/week). An isometric handgrip exercise (IHE) stress echocardiography test was performed in all of them. Both groups showed a similar and statistically significant increase in heart rate, systolic, diastolic, and mean arterial pressure following IHE. The group of active men under study did not show a statistically significant change in the ratio of early diastolic mitral valve inflow velocity to early diastolic lateral wall tissue velocity (E/e' ratio) in response to IHE. Conversely, the inactive participants' E/e' ratio was higher at peak activity in the isometric handgrip exercise. Apparently, healthy middle-aged men with high levels of physical activity seem to have an improved lusitropic cardiac function compared to men with low levels of physical activity, as observed by the different diastolic LV responses induced by isometric handgrip exercise.