Cardiopulmonary exercise test in adults with prior Fontan operation: The prognostic value of serial testing.

The purpose of the study was to determine the role of cardiopulmonary exercise test (CPET) indices in predicting cardiovascular adverse events (CAEs) in patients with Fontan palliation. CAE was defined as death or cardiac surgery. Retrospective review of adult Fontan patients who had treadmill CPET at Mayo Clinic, 1994-2013. Patients with loss of follow-up defined as ≥2years without clinical follow-up were excluded. The results of serial CPETs were reviewed, and patients with CPETs meeting the following criteria were selected for analysis: maximum effort on serial CPETs, minimum of 3-year interval between CPETs, and absence of CAE between CPETs. A total of 145 patients met inclusion criteria for the study; age at baseline CPET was 24±3years; age at Fontan operation was 11±5years; and 91 (63%) were males. Baseline peak oxygen consumption (VO2) was 22.7±5.4ml/kg/min (63±11% predicted), peak heart rate was 135±31beats per minute, and oxygen saturation at peak exercise was 86±7%. Serial CPETs were performed in 71/145 patients (49%); mean duration between CPETs was 3.8±0.3years. The % predicted peak VO2 decreased by 1.7±0.9 percentage points/year. CAE (deaths n=22; cardiac surgery n=45) occurred in 54/145 patients (37%) within 8±3years. Decline in % predicted peak VO2≥3 percentage points/year was the only predictor of 5-year risk of CAE (HR 1.86, 95% CI 1.11-3.48, P=0.02). Serial CPET is prognostic of CAE in the adult Fontan population, and can be used to risk stratify these patients.

Egbe AC ，Driscoll DJ ，Khan AR ，Said SS ，Akintoye E ，Berganza FM ，Connolly HM ... -  《-》

Cardiopulmonary exercise testing in the evaluation of liver disease in adults who have had the Fontan operation.

Liver disease (LD) is a long-term complication in patients with a single ventricle who have had the Fontan operation. A decline in cardiopulmonary exercise testing (CPET) variables is associated with increased risk of hospitalization, but its association with LD is unknown. To determine the association between CPET variables and LD in adults who have had the Fontan operation. We retrospectively reviewed the medical records from two tertiary institutions. We identified 114 adults (≥18 years; mean 30.9±7.4 years) who had undergone the Fontan operation: 56% were women; 63% had total cavopulmonary connection; 66% had New York Heart Association (NYHA) class I status; 42% had arrhythmias; 22% had systemic right ventricle; and 35% had ventricular dysfunction. Of 81 patients with liver-imaging data, 41% had LD (i.e. imaging evidence of cirrhosis, with or without portal hypertension, splenomegaly or varices). There were no differences in clinical or echocardiographic variables between those with and without LD. Among the 58 patients with CPET data, mean peak oxygen consumption (VO2) was 18.6±5.7mL/kg/min, per-cent-predicted peak VO2 was 53.9±15.5%, peak oxygen pulse was 9.3±2.9mL/beat and per-cent-predicted peak oxygen pulse was 82.6±21.5%. Of the 44 patients with liver and CPET data, each standard deviation decrease in per-cent-predicted peak VO2 (16%) and per-cent-predicted peak oxygen pulse (22%) was associated with a 2.3-fold increase in the odds of LD, after adjusting for NYHA, institution and Fontan type (P=0.04). Similarly, each standard deviation decrease in per-cent-predicted peak VO2 and oxygen pulse was associated with an estimated 5.9-year and 4.9-year earlier onset of LD, respectively (P>0.05). Decline in per-cent-predicted peak VO2 and oxygen pulse was associated with increased odds of LD in adults who had undergone the Fontan operation. Our study supports more rapid hepatic evaluation among patients with abnormal or worsening CPET variables.

Agarwal A ，Cunnington C ，Sabanayagam A ，Zier L ，McCulloch CE ，Harris IS ，Foster E ，Atkinson D ，Bryan A ，Jenkins P ，Dua J ，Parker MJ ，Karunaratne D ，Moore JA ，Meadows J ，Clarke B ，Hoschtitzky JA ，Mahadevan VS ... -  《-》

When is the right time for Fontan conversion? The role of cardiopulmonary exercise test.

To determine if Fontan conversion (FC) resulted in improvement in exercise capacity (EC), and to determine the role of cardiopulmonary exercise test (CPET) in risk stratification of patients undergoing FC. A retrospective review of patients who underwent CPET prior to FC at Mayo Clinic from 1994 to 2014. The patients who also underwent post-operative CPET were selected for the analysis of improvement in EC defined as 10% increase in baseline peak oxygen consumption (VO2). 75 patients CPET prior to FC; mean age 24±6years; 44 males (59%); and 51 (68%) were in NYHA III/IV prior to FC. Pre-operative peak VO2 was 15.5±3.4ml/kg/min. A comparison of pre- and post-FC CPET data was performed using 42 patients (56%) that underwent CPET after FC. Improvement in EC occurred in 18 of 42 patients (43%). Baseline peak VO2 >14ml/kg/min was associated with improved EC (hazard ratio [HR] 1.85; P=.02). Improvement in New York Heart Association (NYHA) class occurred in 12 (67%) patients with improved EC vs 2 (8%) without improved EC. Improvement in NYHA class was more likely to occur in patients with improved EC compared to those without improvement EC (odds ratio 4.11, P=.01). There were 10 (13%) perioperative deaths, and baseline peak VO2 ≤14ml/kg/min was predictive of perioperative mortality (HR 3.74; P<.001). Baseline peak VO2 was predictive of perioperative survival, and improvement in EC. Performance on CPET in failing Fontan patients might be a useful clinical parameter in determining appropriate timing of FC.

Egbe AC ，Connolly HM ，Dearani JA ，Bonnichsen CR ，Niaz T ，Allison TG ，Johnson JN ，Poterucha JT ，Said SM ，Ammash NM ... -  《-》

Mechanism for temporal changes in exercise capacity after Fontan palliation: Role of Doppler echocardiography.

The objective was to better understand Doppler hemodynamics and exercise capacity in patients with Fontan palliation by delineating the hemodynamic mechanism for temporal changes in their peak oxygen consumption (V̇o2). We performed a retrospective review of adult Fontan patients with systemic left ventricle (LV) who underwent serial transthoracic echocardiograms (TTE) and cardiopulmonary exercise tests (CPET) at Mayo Clinic in 2000-2015. TTE and CPET data were used (1) to determine agreement between V̇o2 and Doppler-derived LV function indices (eg, stroke volume index [SVI] and cardiac index [CI]) and (2) to determine agreement between temporal changes in peak V̇o2 and LV function indices. Seventy-five patients (44 men; 59%) underwent 191 pairs of TTE and CPET. At baseline, mean age was 24±3 years, peak V̇o2 was 22.9±4.1 mL/kg/min (63±11 percent predicted), SVI was 43±15 mL/m2, and CI was 2.9±0.9 L/min/m2. Peak V̇o2 correlated with SVI (r=0.30, P<.001) and with CI (r=0.45, P<.001) in the 153 pairs of TTE and CPET in patients without cirrhosis. Temporal changes in percent predicted peak V̇o2 correlated with changes in SVI (r=0.48, P=.005) and CI (r=0.49, P=.004) among the 33 patients without interventions during the study. In the 19 patients with Fontan conversion, percent predicted peak V̇o2 and chronotropic index improved. Overall, there was a temporal decline in peak V̇o2 that correlated with decline in Doppler SVI. In the patients who had Fontan conversion operation, there was a temporal improvement in peak V̇o2 that correlated with improvement in chronotropic index.

Egbe A ，Khan AR ，Miranda WR ，Ammash NM ，Warnes CA ，Said SS ，Taggart NW ，Akintoye E ，Veldtman GR ，Connolly HM ... -  《-》

Decline in peak oxygen consumption over time predicts death or transplantation in adults with a Fontan circulation.

Peak oxygen consumption (pVO2) measured by cardiopulmonary exercise test (CPET) predicts mortality in adults with a Fontan circulation. The purpose of this study was to assess the additive prognostic value of change in pVO2 over time. We analyzed a cohort of adults (≥18 years old) with a Fontan circulation who underwent at least 2 maximal CPETs separated by 6-30 months at Boston Children's Hospital between 2000 and 2015. Survival analysis was performed to determine whether changes in CPET variables, including pVO2 between consecutive tests, were associated with subsequent clinical events. The primary outcome was transplant-free survival. The study included 130 patients with 287 CPET test pairs. Average age was 26.6±9.5 years. Baseline pVO2 averaged 22.0±5.7 mL/kg/min or 60.9%±13.7% predicted. In the cohort overall, there was no change in mean pVO2 between sequential CPETs. Eleven patients died and 2 underwent transplant. On average, pVO2 declined for patients who subsequently died or underwent transplant but remained stable among those who did not (-9.8%±14.6% vs 0.0±13.0%, P<.01). Those with a decline in pVO2 between CPETs were at greater risk of death or transplantation (per 10% decrease in pVO2: HR=2.0, 95% CI 1.2-3.1, P=.004). Change in pVO2 remained a significant predictor of death or transplant after adjusting for pVO2 at first CPET (per 10% decline in pVO2: HR=2.5, 95% CI 1.5-4.2, P<.001). A decline in pVO2 between consecutive CPETs predicts increased risk for death or transplant in adults with a Fontan circulation independent of baseline pVO2. These results support the additive clinical value of serial CPET in this population.

Cunningham JW ，Nathan AS ，Rhodes J ，Shafer K ，Landzberg MJ ，Opotowsky AR ... -  《-》