Jain, C. Charles

Importance Reduced heart rate during exercise is common and associated with impaired aerobic capacity in heart failure with preserved ejection fraction (HFpEF), but it remains unknown if restoring exertional heart rate through atrial pacing would be beneficial. Objective To determine if implanting and programming a pacemaker for rate-adaptive atrial pacing would improve exercise performance in patients with HFpEF and chronotropic incompetence. Design, Setting, and Participants Single-center, double-blind, randomized, crossover trial testing the effects of rate-adaptive atrial pacing in patients with symptomatic HFpEF and chronotropic incompetence at a tertiary referral center (Mayo Clinic) in Rochester, Minnesota. Patients were recruited between 2014 and 2022 with 16-week follow-up (last date of follow-up, May 9, 2022). Cardiac output during exercise was measured by the acetylene rebreathe technique. Interventions A total of 32 patients were recruited; of these, 29 underwent pacemaker implantation and were randomized to atrial rate responsive pacing or no pacing first for 4 weeks, followed by a 4-week washout period and then crossover for an additional 4 weeks. Main Outcomes and Measures The primary end point was oxygen consumption (V̇ o 2 ) at anaerobic threshold (V̇ o 2,AT ); secondary end points were peak V̇ o 2 , ventilatory efficiency (V̇ e /V̇ co 2 slope), patient-reported health status by the Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ-OSS), and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Results Of the 29 patients randomized, the mean age was 66 years (SD, 9.7) and 13 (45%) were women. In the absence of pacing, peak V̇ o 2 and V̇ o 2 at anaerobic threshold (V̇ o 2,AT ) were both correlated with peak exercise heart rate ( r = 0.46-0.51, P < .02 for both). Pacing increased heart rate during low-level and peak exercise (16/min [95% CI, 10 to 23], P < .001; 14/min [95% CI, 7 to 21], P < .001), but there was no significant change in V̇ o 2,AT (pacing off, 10.4 [SD, 2.9] mL/kg/min; pacing on, 10.7 [SD, 2.6] mL/kg/min; absolute difference, 0.3 [95% CI, −0.5 to 1.0] mL/kg/min; P = .46), peak V̇ o 2 , minute ventilation (V̇ e) /carbon dioxide production (V̇ co 2 ) slope, KCCQ-OSS, or NT-proBNP level. Despite the increase in heart rate, atrial pacing had no significant effect on cardiac output with exercise, owing to a decrease in stroke volume (−24 mL [95% CI, −43 to −5 mL]; P = .02). Adverse events judged to be related to the pacemaker device were observed in 6 of 29 participants (21%). Conclusions and Relevance In patients with HFpEF and chronotropic incompetence, implantation of a pacemaker to enhance exercise heart rate did not result in an improvement in exercise capacity and was associated with increased adverse events. Trial Registration ClinicalTrials.gov Identifier: NCT02145351

Objectives Fontan-associated liver disease (FALD) is universal post-Fontan palliation; however, its impact on survival remains controversial and current diagnostic tools have limitations. We aimed to assess the prognostic role of liver fibrosis scores (aminotransferase to platelet ratio [APRI] and fibrosis-4 [FIB-4]) and their association with haemodynamics and other markers of liver disease. Methods 159 adults (age ≥18 years) post-Fontan undergoing catheterisation at Mayo Clinic, Minnesota, between 1999 and 2017 were included. Invasive haemodynamics and FALD-related laboratory, imaging and pathology data were documented. Results Mean age was 31.5±9.3 years, while median age at Fontan procedure was 7.5 years (4–14). Median APRI score (n=159) was 0.49 (0.33–0.61) and median FIB-4 score (n=94) was 1.12 (0.71–1.65). Correlations between APRI and FIB-4 scores and Fontan pressures (r=0.30, p=0.0002; r=0.34, p=0.0008, respectively) and pulmonary arterial wedge pressure (r=0.25, p=0.002; r=0.30, p=0.005, respectively) were weak. Median average hepatic stiffness by magnetic resonance elastography was 4.9 kPa (4.3–6.0; n=26) and 24 (77.4%) showed stage 3 or 4 liver fibrosis on biopsy; these variables were not associated with APRI/FIB-4 scores. On multivariable analyses, APRI and FIB-4 scores were independently associated with overall mortality (HR 1.31 [1.07–1.55] per unit increase, p=0.003; HR 2.15 [1.31–3.54] per unit increase, p=0.003, respectively). Conclusions APRI and FIB-4 scores were associated with long-term all-cause mortality in Fontan patients independent of other prognostic markers. Correlations between haemodynamic status and liver scores were weak; furthermore, most markers of liver fibrosis failed to correlate with non-invasive indices, underscoring the complexity of FALD.

Background: There are limited data about the stage D heart failure (advanced HF) in adults with congenital heart disease. Our study objectives were (1) to determine the incidence of new-onset advanced HF in patients and the relationship between advanced HF and all-cause mortality and (2) to determine the relationship between therapies for advanced HF and all-cause mortality. Methods: Retrospective cohort study of adults with congenital heart disease at Mayo Clinic (2003–2019). We defined advanced HF using the European Society of Cardiology diagnostic criteria for advanced HF. Therapies received by the patients with advanced HF were classified into 3 mutually exclusive groups (treatment pathways): (1) conventional cardiac intervention, (2) transplant listing, and (3) palliative care. Results: Of 5309 patients without advanced HF at baseline assessment, 432 (8%) developed advanced HF during follow-up (1.1%/y), and the incidence of advanced HF was higher in patients with severe or complex congenital heart disease. Onset of advanced HF was associated with 6-fold increase in the risk of mortality. Conventional cardiac intervention was associated with significantly higher risk of mortality as compared to transplant listing. The longer the interval from the initial onset of advanced HF to transplant evaluation, the lower the odds of being listed for transplant. Conclusions: Based on these data, we postulate that early identification of patients with advanced HF, and a timely referral for transplant evaluation (instead of conventional cardiac intervention) may offer the best chance of survival for these critically ill patients. Further studies are required to validate this postulation.

Background: Unrepaired truncus arteriosus (TA) carries poor prognosis due to complications of unrestricted pulmonary flow, truncal valve insufficiency, and pulmonary vascular disease. Currently, the hemodynamic profile of adults late after TA repair is unknown. We reviewed the hemodynamics, prevalence, and pathophysiology of pulmonary hypertension (PH) in this population. Methods: Eighteen adult patients with repaired TA who underwent cardiac catheterization at Mayo Clinic, MN, between 1997 and 2021 were identified. PH was defined as either precapillary (mean pulmonary artery pressure [mPAP] ≥25 mm Hg, pulmonary artery wedge pressure [PAWP] ≤15 mm Hg, and pulmonary vascular resistance [PVR] >3 Wood units), isolated postcapillary (mPAP ≥25, PAWP >15, PVR ≤3), or combined (mPAP ≥25, PAWP >15, and PVR >3). Diastolic pressure and transpulmonary gradients were used as ancillary data for classification. Results: Mean age at catheterization was 34 ± 10 years. Mean right ventricular (RV) systolic pressure was 82 ± 22.6 mm Hg, mean right and left mPAPs 28.1 ± 16.2 and 27.9 ± 11.9 mm Hg, respectively. Seven patients (41.2%) had PAWP >15 mm Hg and, among those undergoing arterial catheterization, 7 (53.8%) had a left ventricular (LV) end-diastolic pressure >15 mm Hg. PH was diagnosed in 13 patients (72.2%): 6 (33.3%) precapillary, 4 (22.2%) isolated postcapillary, and 3 (16.7%) combined. PAWP >15 mm Hg was associated with male sex ( P = .049), <moderate RV dysfunction ( P = .049), and lesser RV conduit mean systolic gradient ( P = .02). Patients with PH with precapillary component were older at catheterization ( P = .046). Conclusions: In adults with repaired TA, precapillary PH was only present in one-third of patients with mPAPs not significantly increased in most, whereas elevated PAWP and left-heart disease were common.

Background: The purpose of this study was to assess the relationship between exercise-induced hypertension (EIH) and cardiovascular events, and to determine whether exercise blood pressure (BP) improved risk stratification in adults with repaired coarctation of aorta. Methods: Retrospective study of patients with repaired coarctation of aorta on antihypertensive therapy that underwent exercise testing and exercise test (2003–2019). BP was measured at rest in 3 different clinical settings and averaged to determine the resting BP. Indices of left ventricular function and afterload were obtained from the echocardiogram. EIH was defined as systolic BP >210 (males) or >190 (females) at peak exercise. Cardiovascular event was defined as atrial fibrillation, ventricular tachycardia, heart failure hospitalization, heart transplant, and cardiovascular death. Results: Of 327 patients (age 35±13 years), 116 (35%) had EIH. Although the resting BP was similar between patients with versus without EIH, the EIH group had higher pulsatile arterial load, more advanced left ventricular remodeling, and were less likely to be on angiotensin converting enzyme inhibitor/angiotensin receptor blocker. EIH was associated with cardiovascular events (hazard ratio, 1.06 [95% CI, 1.02–1.08]) independent of resting systolic BP, and improved prognostic accuracy above resting systolic BP ( C statistic, 0.671 [95% CI, 0.645–0.694] to 0.727 [95% CI, 0.709–0.750]; P =0.01). Angiotensin-converting enzyme inhibitor/angiotensin receptor blocker was associated with a lower risk of cardiovascular events. Conclusions: EIH was associated with cardiovascular events independent of resting BP, and patients receiving angiotensin-converting enzyme inhibitor/angiotensin receptor blocker had lower risk of cardiovascular events. These data suggest that exercise BP could be used to assess adequacy of antihypertensive therapy, and to guide titration of antihypertensive therapy.

Abstract Aims Despite their universal predisposition, diagnosing diastolic dysfunction in patients post-Fontan palliation is challenging. Our aim was to compare exercise haemodynamics between adults post-Fontan and patients with heart failure with preserved ejection fraction (HFpEF) and non-cardiac dyspnoea (NCD). Methods and results Twenty-four adults (age ≥18 years) post-Fontan palliation with resting and exercise pulmonary artery wedge pressure (PAWP) measured during supine biking were identified. Forty-eight patients with HFpEF and 48 with NCD diagnosed at catheterization were selected for comparison. Mean age for Fontan patients was 30.3 ± 7.5 years; median ventricular ejection fraction was 52.5% (45–55.8), being &lt;50% in 37.5%. Resting PAWP among Fontan patients was 10.2 ± 3.5 mmHg (&gt;12 mmHg in 25%); PAWP was lower in Fontan patients than in HFpEF but higher than NCD. During exercise, PAWP was lower in the Fontan group than HFpEF (22.5 mmHg [19.3–28] vs. 28.2 ± 6.3; p = 0.0006) but higher than NCD (11.2 ± 4.2, p ≤ 0.0001). However, there were no differences in ΔPAWP/ΔQs between Fontan and HFpEF patients (4.0 [2.1–7.3] vs. 2.7 [1.6–4.4]; p = 0.10) with the ratio being higher post-Fontan than in NCD (0.6 [0.2–1.2]; p &lt; 0.0001). ΔPAWP/ΔQs remained similar between HFpEF and Fontan patients even when those with ejection fraction &lt;50% were excluded (2.7 [1.6–4.4] vs. 2.7 [1.0–5.8]; p = 0.97). Conclusion There were no differences in ΔPAWP/ΔQs ratios between post-Fontan and HFpEF patients, supporting markedly abnormal single ventricle compliance despite lower resting and exercise PAWP. Therefore, exercise invasive haemodynamics may represent a novel tool for the diagnosis of diastolic dysfunction in Fontan patients.

Abstract Aims Systolic dysfunction of the systemic right ventricle (sRV) is common in adults with transposition of the great arteries and sRV. In acquired disease, diastology analysis for assessment of filling pressures (FP) is paramount in patient care. Methods and results Retrospective analysis of 47 adults with sRV without prior systemic tricuspid valve surgery undergoing catheterization and echocardiography within 7 days (median −2 [−1, −3]) from January 2000 to February 2021 at our institution. Median age was 48 (31, 55) years, and 16 (34.0%) patients were female. FPs were normal in 21 patients (44.7%). Left atrial size was enlarged in most patients (83.0%) with mean indexed value 58.3 ± 23.4 mL/m2. Tissue Doppler e′ was not significantly different between those with high FPs vs. normal (medial 0.07 ± 0.03 vs. 0.08 ± 0.03 m/s, P = 0.63; lateral 0.08 ± 0.04 vs. 0.08 ± 0.04 m/s, P = 0.88). E velocity and subpulmonic mitral regurgitant velocity were higher in those with high FPs (0.9 ± 0.3 vs. 0.6 ± 0.2 m/s, P = 0.005; 3.8 ± 1.1 vs. 2.8 ± 0.9 m/s, P = 0.004). Left atrial reservoir strain, sRV global longitudinal strain, and subpulmonic left ventricular strain were worse in those with high FP (18.0 ± 7.6 vs. 27.9 ± 10.2%, P = 0.0009; −13.0 ± 4.4 vs. −17.9 ± 5.0%, P = 0.002; −16.8 ± 5.7 vs. −23.0 ± 3.8%, P = 0.001). Conclusion Despite the complex anatomy, FPs can be assessed non-invasively in adults with sRV without prior systemic tricuspid valve surgery. The current guideline algorithm for diastolic dysfunction in acquired heart disease has limited applicability in this population. Given the limitations of Doppler in this heterogeneous population, strain analysis can be a helpful adjunct for estimation of FPs.

Abstract Aims Conotruncal anomalies share common embryogenic defects of the outflow tracts and great arteries, which result in a predisposition to aortic aneurysms. The purpose of this study was to describe the prevalence and risk of progressive aortic aneurysms in adults with conotruncal anomalies. Methods and results Retrospective study of adults with conotruncal anomalies that underwent cross-sectional imaging 2003–20. Aneurysm was defined as aortic root/mid-ascending aorta &gt;2.1 mm/m2/&gt;1.9 mm/m2, progressive aneurysm as increase by &gt;2 mm, and severe aneurysm as dimension &gt;50 mm. Of 2261 patients (38 ± 12 years; male 58%), 1167 (52%) had an aortic aneurysm, and 205 (14%) had a severe aortic aneurysm. Mean annual increase in aortic root/mid-ascending aorta was 0.3 ± 0.1 mm/0.2 ± 0.1 mm. The 3-, 5-, and 7-year cumulative incidence of the progressive aortic aneurysm was 4%, 7%, and 9%, respectively. The rate of aneurysm growth decreased with age, with no significant growth after age 40 years. There was an excellent correlation between aortic indices from cross-sectional imaging and echocardiography. Of 950 females, 184 had ≥1 pregnancy, and 81 (44%) of the 184 patients had aortic aneurysm prior to pregnancy. There was no aortic dissection or progression of the aortic aneurysm during pregnancy. Overall, there was no aortic dissection during 7984 patient-years of follow-up. Conclusions Aortic aneurysm was common in patients with conotruncal anomalies. However, the risk of progressive aneurysm or dissection was low. Collectively, these data suggest a benign natural history and perhaps a less frequent need for cross-sectional imaging. Further studies are required to determine the optimal timing for surgical intervention in this population.

Background: Chronic elevation of left heart filling pressure causes pulmonary vascular remodeling, pulmonary hypertension, and right heart dysfunction. Although diastolic dysfunction is relatively common in patients with coarctation of aorta, there are limited data about the prevalence and prognostic implications of pulmonary hypertension and right heart dysfunction in this population. The purpose of the study was to assess right heart function and hemodynamics in patients with coarctation of aorta and to determine the relationship between right heart indices and cardiovascular events defined as heart failure hospitalization, heart transplant, or cardiovascular death. Methods: Right heart structure, function, and hemodynamics were assessed with these indices: right atrial volume, right atrial pressure, right atrial reservoir strain, right ventricular global longitudinal strain, right ventricular end-diastolic area, right ventricular systolic pressure, and tricuspid regurgitation severity. Right heart hemodynamic score, range 0 to 5, was generated based on the correlation between the right heart indices and cardiovascular events, using half of the cohort (derivation cohort, n=411), and then tested on the validation cohort (n=410). The goodness of fit and discrimination power was compared using C statistics and risk score. Results: The median follow-up in the derivation cohort was 8.2 (4.0–11.1) years, and 59 (14%) patients had cardiovascular events during this period. Right heart hemodynamic score was independently associated with cardiovascular events (hazard ratio, 1.64 [95% CI, 1.38–2.17]) for every unit increase in right heart hemodynamic score after adjustment for clinical and echocardiographic indices (C statistic, 0.718 [95% CI, 0.682–0.746]). The right heart hemodynamic score was also independently associated with cardiovascular events in the validation cohort (C statistic, 0.711 [95% CI, 0.679–0.741]). The C statistic difference (0.007 [95% CI, 0.014–0.022]) and risk score (0.86 [95% CI, 0.54–1.17]) suggest a good model fit. Conclusions: The current study underscores the prognostic importance of right heart dysfunction in patients with coarctation of aorta and suggests that right heart indices should be used for risks stratification in this population.