Efficacy and Safety of Acoramidis in Transthyretin Amyloid Cardiomyopathy.

BACKGROUND: Transthyretin amyloid cardiomyopathy is characterized by the deposition of misfolded monomeric transthyretin (TTR) in the heart. Acoramidis is a high-affinity TTR stabilizer that acts to inhibit dissociation of tetrameric TTR and leads to more than 90% stabilization across the dosing interval as measured ex vivo. METHODS: In this phase 3, double-blind trial, we randomly assigned patients with transthyretin amyloid cardiomyopathy in a 2:1 ratio to receive acoramidis hydrochloride at a dose of 800 mg twice daily or matching placebo for 30 months. Efficacy was assessed in the patients who had an estimated glomerular filtration rate of at least 30 ml per minute per 1.73 m2 of body-surface area. The four-step primary hierarchical analysis included death from any cause, cardiovascular-related hospitalization, the change from baseline in the N-terminal pro-B-type natriuretic peptide (NT-proBNP) level, and the change from baseline in the 6-minute walk distance. We used the Finkelstein-Schoenfeld method to compare all potential pairs of patients within strata to generate a P value. Key secondary outcomes were death from any cause, the 6-minute walk distance, the score on the Kansas City Cardiomyopathy Questionnaire-Overall Summary, and the serum TTR level. RESULTS: A total of 632 patients underwent randomization. The primary analysis favored acoramidis over placebo (P<0.001); the corresponding win ratio was 1.8 (95% confidence interval [CI], 1.4 to 2.2), with 63.7% of pairwise comparisons favoring acoramidis and 35.9% favoring placebo. Together, death from any cause and cardiovascular-related hospitalization contributed more than half the wins and losses to the win ratio (58% of all pairwise comparisons); NT-proBNP pairwise comparisons yielded the highest ratio of wins to losses (23.3% vs. 7.0%). The overall incidence of adverse events was similar in the acoramidis group and the placebo group (98.1% and 97.6%, respectively); serious adverse events were reported in 54.6% and 64.9% of the patients. CONCLUSIONS: In patients with transthyretin amyloid cardiomyopathy, the receipt of acoramidis resulted in a significantly better four-step primary hierarchical outcome containing components of mortality, morbidity, and function than placebo. Adverse events were similar in the two groups. (Funded by BridgeBio Pharma; ATTRibute-CM ClinicalTrials.gov number, NCT03860935.).

Patisiran Treatment in Patients with Transthyretin Cardiac Amyloidosis.

BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is associated with accumulation of ATTR amyloid deposits in the heart and commonly manifests as progressive cardiomyopathy. Patisiran, an RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this phase 3, double-blind, randomized trial, we assigned patients with hereditary, also known as variant, or wild-type ATTR cardiac amyloidosis, in a 1:1 ratio, to receive patisiran (0.3 mg per kilogram of body weight) or placebo once every 3 weeks for 12 months. A hierarchical procedure was used to test the primary and three secondary end points. The primary end point was the change from baseline in the distance covered on the 6-minute walk test at 12 months. The first secondary end point was the change from baseline to month 12 in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score (with higher scores indicating better health status). The second secondary end point was a composite of death from any cause, cardiovascular events, and change from baseline in the 6-minute walk test distance over 12 months. The third secondary end point was a composite of death from any cause, hospitalizations for any cause, and urgent heart failure visits over 12 months. RESULTS: A total of 360 patients were randomly assigned to receive patisiran (181 patients) or placebo (179 patients). At month 12, the decline in the 6-minute walk distance was lower in the patisiran group than in the placebo group (Hodges-Lehmann estimate of median difference, 14.69 m; 95% confidence interval [CI], 0.69 to 28.69; P = 0.02); the KCCQ-OS score increased in the patisiran group and declined in the placebo group (least-squares mean difference, 3.7 points; 95% CI, 0.2 to 7.2; P = 0.04). Significant benefits were not observed for the second secondary end point. Infusion-related reactions, arthralgia, and muscle spasms occurred more often among patients in the patisiran group than among those in the placebo group. CONCLUSIONS: In this trial, administration of patisiran over a period of 12 months resulted in preserved functional capacity in patients with ATTR cardiac amyloidosis. (Funded by Alnylam Pharmaceuticals; APOLLO-B ClinicalTrials.gov number, NCT03997383.).

Cardiovascular Effects of Oral Ketone Ester Treatment in Patients With Heart Failure With Reduced Ejection Fraction: A Randomized, Controlled, Double-Blind Trial.

BACKGROUND: Heart failure triggers a shift in myocardial metabolic substrate utilization, favoring the ketone body 3-hydroxybutyrate as energy source. We hypothesized that 14-day treatment with ketone ester (KE) would improve resting and exercise hemodynamics and exercise capacity in patients with heart failure with reduced ejection fraction. METHODS: In a randomized, double-blind cross-over study, nondiabetic patients with heart failure with reduced ejection fraction received 14-day KE and 14-day isocaloric non-KE comparator regimens of 4 daily doses separated by a 14-day washout period. After each treatment period, participants underwent right heart catheterization, echocardiography, and blood sampling at plasma trough levels and after dosing. Participants underwent an exercise hemodynamic assessment after a second dosing. The primary end point was resting cardiac output (CO). Secondary end points included resting and exercise pulmonary capillary wedge pressure and peak exercise CO and metabolic equivalents. RESULTS: We included 24 patients with heart failure with reduced ejection fraction (17 men; 65±9 years of age; all White). Resting CO at trough levels was higher after KE compared with isocaloric comparator (5.2±1.1 L/min versus 5.0±1.1 L/min; difference, 0.3 L/min [95% CI, 0.1-0.5), and pulmonary capillary wedge pressure was lower (8±3 mm Hg versus 11±3 mm Hg; difference, -2 mm Hg [95% CI, -4 to -1]). These changes were amplified after KE dosing. Across all exercise intensities, KE treatment was associated with lower mean exercise pulmonary capillary wedge pressure (-3 mm Hg [95% CI, -5 to -1] ) and higher mean CO (0.5 L/min [95% CI, 0.1-0.8]), significantly different at low to moderate steady-state exercise but not at peak. Metabolic equivalents remained similar between treatments. In exploratory analyses, KE treatment was associated with 18% lower NT-proBNP (N-terminal pro-B-type natriuretic peptide; difference, -98 ng/L [95% CI, -185 to -23]), higher left ventricular ejection fraction (37±5 versus 34±5%; P=0.01), and lower left atrial and ventricular volumes. CONCLUSIONS: KE treatment for 14 days was associated with higher CO at rest and lower filling pressures, cardiac volumes, and NT-proBNP levels compared with isocaloric comparator. These changes persisted during exercise and were achieved on top of optimal medical therapy. Sustained modulation of circulating ketone bodies is a potential treatment principle in patients with heart failure with reduced ejection fraction. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05161650.

Does targeted positioning of the left ventricular pacing lead towards the latest local electrical activation in cardiac resynchronization therapy reduce the incidence of death or hospitalization for heart failure?

BACKGROUND: Cardiac resynchronization therapy (CRT) improves symptoms, health-related quality of life and long-term survival in patients with systolic heart failure (HF) and shortens QRS duration. However, up to one third of patients attain no measurable clinical benefit from CRT. An important determinant of clinical response is optimal choice in left ventricular (LV) pacing site. Observational data have shown that achieving an LV lead position at a site of late electrical activation is associated with better clinical and echocardiographic outcomes compared to standard placement, but mapping-guided LV lead placement towards the site of latest electrical activation has never been investigated in a randomized controlled trial (RCT). The purpose of this study was to evaluate the effect of targeted positioning of the LV lead towards the latest electrically activated area. We hypothesize that this strategy is superior to standard LV lead placement. METHODS: The DANISH-CRT trial is a national, double-blinded RCT (ClinicalTrials.gov NCT03280862). A total of 1,000 patients referred for a de novo CRT implantation or an upgrade to CRT from right ventricular pacing will be randomized 1:1 to receive conventional LV lead positioning preferably in a nonapical posterolateral branch of the coronary sinus (CS) (control group) or targeted positioning of the LV lead to the CS branch with the latest local electrical LV activation (intervention group). In the intervention group, late activation will be determined using electrical mapping of the CS. The primary endpoint is a composite of death and nonplanned HF hospitalization. Patients are followed for a minimum of 2 years and until 264 primary endpoints occurred. Analyses will be conducted according to the intention-to-treat principle. Enrollment for this trial began in March 2018, and per April 2023, a total of 823 patients have been included. Enrollment is expected to be complete by mid-2024. CONCLUSIONS: The DANISH-CRT trial will clarify whether mapping-guided positioning of the LV lead according to the latest local electrical activation in the CS is beneficial for patients in terms of reducing the composite endpoint of death or nonplanned hospitalization for heart failure. Results from this trial are expected to impact future guidelines on CRT. GOV IDENTIFIER: NCT03280862.

Strain-derived myocardial work in wild-type transthyretin cardiac amyloidosis with aortic stenosis-diagnosis and prognosis.

BACKGROUND: Several echocardiographic parameters have been suggested to differentiate wild-type transthyretin cardiac amyloidosis (ATTRwt) from other causes of hypertrophy. These studies have all been performed in small samples of mixed cardiac amyloidosis. The purpose of this study was to investigate the role of echocardiographic parameters in patients with ATTRwt and aortic stenosis (AS) versus patients with AS. The secondary aim was to investigate the role of myocardial work in the prognosis of patients with ATTRwt. METHODS: The sensitivity and specificity of the relative apical sparing ratio (RAS), the apical-to-basal ratio (AB), the ejection-fraction-to-global-longitudinal-strain ratio (EF/GLS), and the global myocardial work index (GWI) were calculated using receiver-operated characteristics curves and area under the curve (AUC) in patients with ATTRwt and AS (n = 50) versus patients with AS (n = 354). Multivariable regression was used to assess the prognostic value of GWI in patients with ATTRwt (n = 212). RESULTS: When used to identify AS from ATTRwt + AS, GWI had a sensitivity of 80% and specificity of 70%. The AUC of GWI was larger than that of AB (p = .01) and EF/GLS (p > .01) but not RAS (p = .15). In patients with ATTRwt multivariable regression found age predicted mortality with an estimate of HR = 1.086 (CI: 1.034-1.141) while GWI predicted survival with an estimate of HR = .837 (CI: .733-.956) per 100 mmHg*% increase. CONCLUSION: GWI was demonstrated to be a viable classifier in ATTRwt and AS versus AS. GWI was demonstrated to independently predict survival in patients with ATTRwt. Further studies examining the role of myocardial work in ATTRwt are warranted.

Reduction in myocardial function and oxygen consumption after chemoradiotherapy in patients with esophageal cancer.

BACKGROUND: Chemoradiotherapy (CRT) may induce myocardial dysfunction, congestive heart failure, and impaired physical performance in patients with esophageal cancer (EC). We aimed to investigate left ventricular (LV) function at rest and during stress, using echocardiography (echo) and a cardiopulmonary exercise (CPX) test both before and immediately after completing CRT. MATERIAL AND METHODS: Consecutive EC patients referred for curative treatment were enrolled. Patients attended either definitive CRT or neoadjuvant CRT with subsequent surgery. The evaluation included cardiac biomarkers, electrocardiogram, echo, and CPX test. The primary endpoint was changes in left ventricular (LV) global longitudinal strain (GLS) at rest. Secondary endpoints were LV ejection fraction (LVEF), LV diastolic function, LVEF and GLS at peak exercise, and maximal oxygen consumption (VO2max). The trial was registered with ClinicalTrials.gov (NCT03619317). RESULTS: Among 47 patients enrolled (94% male; median age 67 years, range 50-86 years), cardiac examinations were performed a median of three days [Interquartile range (IQR (1-5))] before CRT and one day [IQR (0-6)] after CRT. At rest, GLS and LVEF decreased, 17.6 vs. 16.4% and 56.4 vs. 55.1%, respectively (p = 0.004; p = 0.030). Furthermore, an absolute decrease of at least 5% in LVEF and 2.5% in GLS was noted in 21% of the patients. Signs of LV diastolic dysfunction increased from 13 to 21% (p = ns). VO2max significantly decreased; 21.2 ml/kg/min vs. 18.8 ml/kg/min (p < 0.001). CONCLUSION: LV function and physical performance decreased in EC patients after CRT, and the LV systolic reserve capacity declined. This study highlighted that EC treatment was associated with early cardiac side effects, which may have clinical and prognostic implications.

Micro- and macrovascular cardiac allograft vasculopathy in relation to 91 cardiovascular biomarkers in heart transplant recipients-An exploratory study.

BACKGROUND: Cardiac allograft vasculopathy (CAV) limits survival after heart transplantation (HTx), and the pathogenesis is not fully clarified. We aimed to investigate a wide range of biomarkers and their correlation with micro- and macrovascular CAV and major adverse cardiac events in HTx patients. METHODS: We evaluated 91 cardiovascular disease-related proteins in 48 HTx patients using a novel proteomic panel. Patients were dichotomized according to micro- and macrovascular CAV burden determined by coronary angiography, optical coherence tomography, and 15 O-H2 O positron emission tomography imaging. Major adverse cardiac events included significant CAV progression, heart failure, treated rejection, and cardiovascular death. RESULTS: We found consistent differences in two proteins involved in cholesterol homeostasis: significantly increased proprotein convertase subtilisin/kexin type 9 (PCSK9) (p < .05) and significantly decreased paraoxonase 3 (PON3) (p < .05). N-terminal pro-brain natriuretic peptide (NT-proBNP) was significantly increased in patients with microvascular CAV (p < .05) and borderline significantly increased in patients experiencing major adverse cardiac events (p = .10) and patients with macrovascular CAV (p = .05). CONCLUSIONS: We identified consistent changes in two proteins involved in cholesterol homeostasis which may be important players in the pathogenesis of CAV: PON3 and PCSK9. NT-proBNP also showed consistent changes across all groups but only reached statistical significance in patients with microvascular CAV. Our results warrant further validation in future studies.

Reverse remodeling of tricuspid valve morphology and function in chronic thromboembolic pulmonary hypertension patients following pulmonary thromboendarterectomy: a cardiac magnetic resonance imaging and invasive hemodynamic study.

BACKGROUND: To investigate changes in tricuspid annulus (TA) and tricuspid valve (TV) morphology among chronic thromboembolic pulmonary hypertension (CTEPH) patients before and 12 months after pulmonary thromboendarterectomy (PEA) and compare these findings to normal control subjects. METHODS: 20 CTEPH patients and 20 controls were enrolled in the study. The patients were examined with echocardiography, right heart catherization and cardiac magnetic resonance imaging prior to PEA and 12 months after. RESULTS: Right atrium (RA) volume was significantly reduced from baseline to 12 months after PEA (30 ± 9 vs 23 ± 5 ml/m2, p < 0.005). TA annular area in systole remained unchanged (p = 0.11) and was comparable to controls. The leaflet area, tenting volume and tenting height in systole were significantly increased at baseline but decreased significantly with comparable values to controls after 12 months (p < 0.005). There was correlation between the changes of right ventricular-pulmonary artery coupling and changes of TV tenting height (r = - 0.54, p = 0.02), TV tenting volume (r = - 0.73, p < 0.001) and TV leaflet area (- 0.57, p = 0.01) from baseline to 12 months after PEA. Tricuspid regurgitation jet area/RA area was significantly (p < 0.01) reduced from baseline (30 ± 13%) to 12 months after PEA (9 ± 10%). CONCLUSION: In CTEPH patients selected for PEA, TV tenting height, volume and valve area are significantly increased whereas annulus size and shape are less affected. The alterations in TV morphology are fully reversed after PEA and correlates to improvements of right ventricular-pulmonary arterial coupling.

Burden of arrhythmia and silent ischemia in heart transplant patients with cardiac allograft vasculopathy.

BACKGROUND: The incidence of sudden cardiac death (SCD) following heart transplantation (HTx) accounts for approximately 10% of post-HTx deaths. Ischemia, brady- and tachy-arrhythmias caused by rejection and cardiac allograft vasculopathy (CAV) seem related to SCD. Hence, we aimed to investigate the relation between CAV, arrhythmias and silent ischemia in long-term HTx patients. Methods. 49 HTx patients were included. Patients were CAV classified in accordance with guidelines from the International Society of Heart and Lung Transplantation. Patients were divided into predefined CAV groups (CAV 0, CAV 1, CAV 2 + 3). Incidences of arrhythmia and silent ischemia were detected by 48-h electrocardiogram monitoring and analyzed blinded to CAV-status. Results. Median time since transplantation was 9 years [IQR 4-14]. We observed a higher incidence of non-sustained ventricular tachycardia (NSVT) in CAV 2 + 3 patients than CAV 0 and 1 patients (p = .01). Likewise, isolated premature ventricular complexes (PVC) (p = .01) and PQ-interval prolongation (p = .01) were more frequent in CAV 2 + 3 patients than CAV 0 and 1 patients. Silent ischemia was only observed among CAV 3 patients (p = .04). We saw no significant difference in the incidence of supraventricular tachycardia among CAV groups (p = .21). Likewise, no difference in the right bundle branch block was observed (p = .68). Conclusion. NSVT was associated with CAV status in long-term HTx patients. Patients with moderate to severe CAV showed higher incidences of PVCs and PQ-interval prolongation than patients with mild or no CAV. Silent ischemia was only seen in patients with severe CAV.

Distribution and prognostic value of left ventricular global longitudinal strain in elderly patients with symptomatic severe aortic stenosis undergoing transcatheter aortic valve replacement.

AIMS: The aim of present study was to examine the preoperative prevalence and distribution of impaired left ventricular global longitudinal strain (LVGLS) in elderly patients with symptomatic aortic stenosis (AS) undergoing transcutaneous aortic valve replacement (TAVR) and to determine the predictive value of LVGLS on survival. METHODS: We included 411 patients with symptomatic severe AS treated with TAVR during a 5-year period, where a baseline echocardiography including LVGLS assessment was available. RESULTS: Mean age was 80.1 ± 7.1 years and aortic valve area (AVA) index 0.4 ± 0.1 cm2. 78 patients died during a median follow-up of 762 days. Mean left ventricular ejection fraction (LVEF) was 50 ± 13% and mean LVGLS was - 14.0%. LVEF was preserved in 60% of patients, while impaired LVGLS > - 18% was seen in 75% of the patients. Previous myocardial infarction, LVEF < 50%, LVGLS > - 14%, low gradient AS (< 4.0 m/s), tricuspid regurgitant gradient > 30 mmHg were identified as significant univariate predictors of all-cause mortality. On multivariate analysis LVGLS > - 14% (HR 1.79 [1.02-3.14], p = 0.04) was identified as the only independent variable associated with all-cause mortality. Reduced survival was observed with an impaired LVGLS > - 14% in the total population (p < 0.002) but also in patients with high AS gradient with preserved LVEF. LVGLS provided incremental prognostic value with respect to clinical characteristics, AVA and LVEF (χ2 19.9, p = 0.006). CONCLUSIONS: In patients with symptomatic AS undergoing TAVR, impaired LVGLS was highly prevalent despite preserved LVEF. LVGLS > - 14% was an independent predictor of all-cause mortality, and survival was reduced if LVGLS > - 14%.

Long-term changes of resting and exercise right ventricular systolic performance in patients with chronic thromboembolic pulmonary hypertension following pulmonary thromboendarterectomy - A two-dimensional and three-dimensional echocardiographic study.

AIMS: To characterize right ventricular (RV) geometry and function in chronic thromboembolic pulmonary hypertension (CTEPH) patients at rest and during exercise before pulmonary thromboendarterectomy (PEA), and at 3 and 12 months after PEA using two-dimensional and three-dimensional echocardiography with reference to clinical performance and exercise capacity. METHODS AND RESULTS: Forty subjects (20 CTEPH patients and 20 controls) were enrolled between December 2014 and January 2017. Three-dimensional echocardiography demonstrated a significant reduction and normalization of end-diastolic and end-systolic RV volumes in CTEPH patients 12 months after PEA. RV systolic function improved after PEA; however, tricuspid annular plane systolic excursion (TAPSE) (baseline 18 ± 6 mm vs 15 ± 3 mm at 12 months after PEA, P < .05) and tricuspid lateral annular systolic velocity (RV-S') (baseline -8.3 ± 2.1 cm/s vs -7.2 ± 1.3 cm/s at 12 months after PEA, P < .05) declined significantly after PEA. Tricuspid regurgitation gradient was 64 ± 21 mm Hg at baseline, 40 ± 14 mm Hg at 3 months, and 30 ± 13 at 12 months, P < .00001. RV free-wall longitudinal strain at peak exercise was significantly increased from baseline (-10.6 ± 5.5%) to 12 months of follow-up (-15.8 ± 5.2%), P < .005. Physical exercise capacity, measured as peak oxygen uptake, was significantly increased and correlated directly with improvement of resting and exercise-induced RV-EF. CONCLUSION: Improvement of RV geometry and systolic function, along with the reduction of systolic pulmonary pressure, can be expected following PEA in CTEPH patients during long-term follow-up. Improvement of RV myocardial contractility after PEA was only revealed at peak exercise over time. Importantly, physical exercise capacity was significantly increased and was found to be directly correlated with improvement of resting and exercise-induced RV-EF.

Test-retest repeatability of myocardial oxidative metabolism and efficiency using standalone dynamic 11C-acetate PET and multimodality approaches in healthy controls.

BACKGROUND: Myocardial efficiency measured by 11C-acetate positron emission tomography (PET) has successfully been used in clinical research to quantify mechanoenergetic coupling. The objective of this study was to establish the repeatability of myocardial external efficiency (MEE) and work metabolic index (WMI) by non-invasive concepts. METHODS AND RESULTS: Ten healthy volunteers (63 ± 4 years) were examined twice, one week apart, using 11C-acetate PET, cardiovascular magnetic resonance (CMR), and echocardiography. Myocardial oxygen consumption from PET was combined with stroke work data from CMR, echocardiography, or PET to obtain MEE and WMI for each modality. Repeatability was estimated as the coefficient of variation (CV) between test and retest. MEECMR, MEEEcho, and MEEPET values were 21.9 ± 2.7%, 16.4 ± 3.7%, and 23.8 ± 4.9%, respectively, P < .001. WMICMR, WMIEcho, and WMIPET values were 4.42 ± 0.90, 4.07 ± 0.63, and 4.58 ± 1.13 mmHg × mL/m2 × 106, respectively, P = .45. Repeatability for MEECMR was superior compared with MEEEcho but did not differ significantly compared with MEEPET (6.3% vs 12.9% and 9.4%, P = .04 and .25). CV values for WMICMR, WMIEcho, and WMIPET were 10.0%, 14.8%, and 12.0%, respectively, (P = .53). CONCLUSIONS: Non-invasive measurements of MEE using 11C-acetate PET are highly repeatable. A PET-only approach did not differ significantly from CMR/PET and might facilitate further clinical research due to lower costs and broader applicability.

Longer inter-lead electrical delay is associated with response to cardiac resynchronization therapy in patients with presumed optimal left ventricular lead position.

Aims: In a randomized trial of cardiac resynchronization therapy (CRT), a presumed optimal left ventricular (LV) lead position close to the latest mechanically activated non-scarred myocardium was achieved in 98% of patients by standard implantation. We evaluated whether inter-lead electrical delay (IED) was associated with response to CRT in these patients. Methods and results: We prospectively included 160 consecutive patients undergoing CRT. Pre-implant speckle-tracking echocardiography radial strain and 99mTc myocardial perfusion imaging determined the latest mechanically activated non-scarred myocardial segment. We measured procedural IED as the time interval between sensed signals in right ventricular and LV lead electrograms. All patients had LV pacing site concordant or adjacent to the latest mechanically activated non-scarred segment verified by cardiac computed tomography. Response to CRT was defined as ≥15% reduction in LV end-systolic volume at 6 months follow-up. Selecting a practical IED cut-off value of 100 ms, more patients with long IED than patients with short IED responded to CRT (87 vs. 68%; P = 0.004). In multivariate logistic regression analysis, IED ≥100 ms remained associated with CRT response after adjusting for baseline characteristics, including QRS duration and scar burden [odds ratio 3.19 (1.24-8.17); P = 0.01]. Categorizing IED by tertiles, CRT response improved with longer IED (P = 0.03). Comparable response rates were observed in patients with a concordant and adjacent LV lead position. Conclusion: A longer IED was associated with more pronounced LV reverse remodelling response in CRT recipients with a presumed optimal LV lead position concordant or adjacent to the latest mechanically activated non-scarred segment.

Donor-specific antibodies are associated with micro- and macrovascular coronary disease, restrictive myocardial damage, and poor outcome in heart-transplanted patients.

AIMS: We examined the relationship between donor-specific HLA antibody (DSA) presence and graft function, hemodynamics, cardiac allograft vasculopathy (CAV), and major adverse cardiac events (MACE) in stable long-term heart-transplanted (HTx) patients. METHODS: Sera from 79 patients (median 7.5 years after HTx) were analyzed for DSA presence. Graft function was evaluated by echocardiography and right heart catheterization. CAV burden was determined by coronary angiography, optical coherence tomography (OCT), and coronary flow velocity reserve (CFVR). Patients were prospectively followed after DSA assessment. MACE included significant CAV progression, heart failure, treated rejection, and cardiovascular death. RESULTS: Sixty patients had no DSA, and 19 patients were sensitized. The vasculopathy burden by angiography, OCT, and CFVR was more pronounced in DSA-positive patients than in DSA-negative patients. DSA-positive patients had higher pulmonary capillary wedge pressure (16 [8; 21] vs 9 mm Hg [7; 11], P<.05) and right atrial pressure (8 [6; 9] vs 4 mm Hg [2; 6], P<.01) and lower global longitudinal strain (-13% [-10; -15] vs -16% [-14; -17], P<.01) than DSA-negative patients. DSA presence was a strong MACE predictor (HR 4.7 (95% CI 2.0-11.4), P<.001). CONCLUSIONS: DSA-positive patients had higher vasculopathy burden, higher filling pressures, and lower longitudinal myocardial deformation than DSA-negative patients. The DSA presence was a strong MACE predictor.

Echocardiographic assessment of right heart function in heart transplant recipients and the relation to exercise hemodynamics.

This study aimed to characterize right heart function in heart transplantation (HTx) patients using advanced echocardiographic assessment and simultaneous right heart catheterization (RHC). Comprehensive two-dimensional (2D) and three-dimensional (3D) echocardiographic assessment of right heart function was performed in 105 subjects (64 stable HTx patients and 41 healthy controls). RHC was performed at rest and during semi-supine maximal exercise test. Compared with controls, in conclusion, HTx patients had impaired right ventricle (RV) systolic function in terms of decreased RV-free wall (FW) global longitudinal strain (GLS) (-20 ± 5% vs. -28 ± 5%, P < 0.0001) and 3D-ejection fraction (EF) (50 ± 8% vs. 60 ± 6%, P < 0.0001). In HTx patients, echocardiographic RV systolic function was significantly correlated with NYHA-class (3D-RVEF: r = -0.62, P < 0.0001; RV-FW-GLS: r = -0.41, P = 0.0009) and cardiac allograft vasculopathy (3D-RVEF: r = -0.42, P = 0.0005; RV-FW-GLS: r = -0.25, P = 0.0444). RHC demonstrated a good correlation between invasively assessed resting RV-stroke volume index and exercise capacity (r = 0.58, P < 0.0001) and NYHA-class (r = -0.41, P = 0.0009). RV systolic function is reduced in HTx patients compared with controls. 3D RVEF and 2D longitudinal deformation analyses are associated with clinical performance in stable HTx patients and seem suitable in noninvasive routine right heart function evaluation after HTx. Invasively assessed RV systolic reserve was strongly associated with exercise capacity.

Clinical features, exercise hemodynamics, and determinants of left ventricular elevated filling pressure in heart-transplanted patients.

This study aimed to assess clinical, functional, and hemodynamic characteristics of heart-transplanted (HTX) patients during exercise. We performed comprehensive echocardiographic graft function assessment during invasive hemodynamic semi-supine exercise test in 57 HTX patients. According to hemodynamics findings, patients were divided into Group A: normal left ventricular (LV) filling pressure (FP): pulmonary capillary wedge pressure (PCWP) <15 mmHg at rest and <25 mmHg at peak exercise, and Group B: elevated LV-FP: PCWP ≥15 mmHg at rest or ≥25 mmHg at peak exercise. Thirty-one patients (54%) had normal LV-FP and 26 patients (46%) had elevated LV-FP. The latter had higher cumulative rejection burden (P < 0.01) and were more symptomatic (NYHA class >1) (P < 0.05), and cardiac allograft vasculopathy (CAV) was more prevalent (P < 0.05). With exercise, the changes in both left- and right-sided filling pressures were significantly increased, whereas LV longitudinal myocardial deformation was lower (P < 0.05) in patients with elevated LV-FP than in patients with normal LV-FP. No between-group difference was observed for cardiac index or LV ejection fraction (LVEF) during exercise. In conclusion, elevated LV-FP can be demonstrated in approximately 50% of HTX patients. Patients with elevated LV-FP have impaired myocardial deformation capacity, higher prevalence of CAV, and higher rejection burden, and were more symptomatic. Exercise test with the assessment of longitudinal myocardial deformation should be considered in routine surveillance of HTX patients as a marker of restrictive filling (ClinicalTrials.gov Identifier: NCT02077764).

Coronary Flow Reserve Predicts Longitudinal Myocardial Deformation Capacity in Heart-Transplanted Patients.

AIMS: This study aimed to evaluate the role of microvascular dysfunction on left ventricular (LV) longitudinal deformation, filling pressures, and exercise capacity in heart-transplanted (HTx) patients. METHODS AND RESULTS: Fifty-seven HTx patients underwent comprehensive echocardiographic graft function assessment during symptom-limited, semisupine exercise test with simultaneous right heart catheterization. Coronary flow velocity reserve (CFVR) was measured in the left anterior descending artery using pulsed Doppler echocardiography. We divided patients into two groups based on upper and lower median of CFVR. Twenty-six healthy subjects served as controls. Compared with healthy controls, HTx patients had reduced CFVR (P < 0.0001), exercise capacity (P < 0.0001), and LV longitudinal deformation capacity (P < 0.0001). HTx patients in the reduced CFVR group (CFVR < 2.73) were more symptomatic (P < 0.0001) and had higher prevalence of coronary cardiac allograft vasculopathy (CAV) (P < 0.0001) than patients in the high CFVR group. Systolic function improved in both HTx groups during exercise. However, LV longitudinal myocardial deformation improved significantly more in the high CFVR group (P < 0.0001). Peak exercise LV global longitudinal strain and CFVR were strongly correlated (r = 0.8, P < 0.0001). A weak correlation was observed between CFVR and invasive cardiac index at peak exercise (r = 0.35, P < 0.01) and CFVR and LV filling measured by E/e' ratio (r = -0.41, P < 0.01) and pulmonary capillary wedge pressure (r = -0.30, P < 0.05). CONCLUSION: HTx patients have reduced CFVR, exercise capacity, and LV longitudinal myocardial deformation capacity compared with healthy individuals. HTx patients with reduced CFVR are more symptomatic and have increased prevalence of CAV. Furthermore, reduced CFVR is correlated with reduced LV longitudinal myocardial deformation and exercise capacity.

The long-term influence of repetitive cellular cardiac rejections on left ventricular longitudinal myocardial deformation in heart transplant recipients.

The aim of the study was to evaluate the long-term influence of repeated acute cellular rejections on left ventricular longitudinal deformation in heart transplantation (HTX) patients. One hundred and seventy-eight HTX patients were included in the study. Rejections were classified according to the International Society of Heart and Lung Transplantation (ISHLT) classification (0R-3R). Patients were divided into three groups according to rejection scores (RSs). Group 1: <50% of biopsies with 1R rejection and no ≥2R rejections; Group 2: ≥50% of biopsies with 1R rejection or one biopsy with ≥2R rejection; Group 3: ≥Two biopsies with ≥2R rejections. All patients had a comprehensive echocardiographic examination and coronary angiography. We found significantly decreasing global longitudinal strain (GLS) comparing to rejection groups (GLS group 1: -16.8 ± 2.4 (%); GLS group 2: -15.9 ± 3.3 (%); GLS group 3: -14.5 ± 2.9 (%), P = 0.0003). After excluding patients with LVEF < 50% or vasculopathy, GLS was still significantly reduced according to RS groups (P = 0.0096). Total number of 1R and 2R rejections correlated significant to GLS in a linear regression model. In contrast, we found fractional shortening and LVEF to be unaffected by repeated rejections. In conclusion, repeated cardiac rejections lead to impaired graft function as detected by decreasing magnitude of GLS. In contrast, traditional systolic graft function surveillance by LVEF did not correlate to rejection burden.

Familial occurrences of cardiac wild-type transthyretin amyloidosis: a case series.

Background: Cardiomyopathy caused by aggregation and deposition of transthyretin amyloid fibrils in the heart (ATTR-CM) is divided into a hereditary (ATTRv) and a wild-type (ATTRwt) forms. While ATTR-CM has been considered a rare disease, recent studies suggest that it is severely underdiagnosed and an important cause of heart failure in elderly patients. Familial occurrence is implicit in ATTRv, but it is not expected in ATTRwt. Case summary: We report a case series of two unrelated families each with two brothers diagnosed with ATTRwt. Genetic testing did not reveal mutations in the transthyretin gene. Family screening with electrocardiogram, echocardiography, and genetic testing did not raise any suspicion of ATTR in first-line family members. Discussion: Familial occurrence of a rare, non-hereditary disease is statistically unlikely. Two siblings in two different families diagnosed with ATTRwt highlight that the aetiology of ATTRwt is poorly understood, and that genetic factors distinct from mutations in the transthyretin gene, as well as environmental factors, might contribute to the pathogenesis. Identifying such factors might reveal new therapeutic targets. To investigate this further, clinicians need to be aware of the possibility of familial occurrence of ATTRwt.

Exercise Hemodynamics and Mitochondrial Oxidative Capacity in Disease Stages of Wild-Type Transthyretin Amyloid Cardiomyopathy.

BACKGROUND: Wild-type transthyretin amyloid (ATTRwt) cardiomyopathy is increasingly recognized in the development of heart failure. The link between cardiac performance, hemodynamics, and mitochondrial function in disease stages of ATTRwt has not previously been studied but may provide new insights into the pathophysiology and clinical performance of the patients. METHODS AND RESULTS: The study investigated 47 patients diagnosed with ATTRwt at Aarhus University Hospital, Denmark. Patients were stratified according to the disease stages of the National Amyloidosis Centre (NAC) as NAC I with low levels of NT-proBNP (N-terminal pro-B-type natriuretic peptide) (NAC I-L, n=14), NAC I with high levels NT-proBNP (NAC I-H, n=20), and NAC II-III (n=13). Exercise testing with simultaneous right heart catheterization was performed in all patients. Endomyocardial biopsies were collected from the patients and the mitochondrial oxidative phosphorylation capacity was assessed. All NAC disease groups, even in the NAC I-L group, a significant abnormal increase in biventricular filling pressures were noted during exercise while the filling pressures was normal or near normal at rest. The inotropic response to exercise was reduced with diminished increase in cardiac output which was significantly more pronounced in the NAC I-H (Diff. -2.4, 95% CI (-4.2: -0.7), P=0.00) and the NAC II-III group (Diff: -3.1 L/min, 95% CI (-5.2: -1.1), P=0.00) compared with the NAC I-L group. The pulmonary artery wedge pressure to cardiac output ratio at peak exercise was significantly different between NAC I-L and NAC II-III (Diff: 1.6 mm Hg*min/L, 95% CI (0.01:3.3, P=0.04)). Patients with ATTRwt had a reduced oxidative phosphorylation capacity which correlated to left ventricular mass but not to cardiac output capacity. CONCLUSIONS: An abnormal restrictive left ventricle and right ventricle response to exercise was demonstrated, even present in patients with early-stage ATTRwt. In more advanced disease stages a progressive impairment of the pressure-flow relationship was noted. The myocyte energetics is deranged but not associated to the contractile reserve or restrictive filling characteristics in ATTRwt.