Category Archives: Abstracts

Anaerobic Threshold (AT) is an independent predictor of medium term survival following elective endovascular repair of abdominal aortic aneurysm (EVAR)

Dawkins C, Hollingsworth AC, Walker P, Milburn S, Danjoux G,Cheesman M, Mofidi R

J Cardiovasc Surg (Torino). 2019 Oct 4. doi: 10.23736/S0021-9509.19.11052-X.
[Epub ahead of print]

BACKGROUND: The aim of this study was to examine the value preoperative AT as
predictor of postoperative survival in patients who underwent elective EVAR for
repair of asymptomatic AAA.
METHODS: Consecutive patients who underwent elective EVAR between 2008 and 2018
were analysed. Cardiopulmonary exercise testing was performed. Perioperative/30
day mortality was compared between patients who had AT ≥8 ml kg-1 min-1 and those
with AT<8 ml kg-1 min-1. Risk factors for postoperative survival following EVAR
were examined using Cox’s regression analysis.
RESULTS: Between 1st January 2008 and 31st December 2017, 430 patients underwent
elective EVAR (standard device: 374, fenestrated/ branched: 56), [Median age: 76
years (range: 53-91)]. Median AT was 9.3 (range: 5.4-16.1). 30-day mortality was
0.9%. These patients were followed up for a median of 1630 days. There was no
significant difference in perioperative/30 day mortality between patients who had
AT≥8 and those who had AT<8 (χ2=1.56, P=0.22). Age [HR:1.51 (CI: 1.07-1.99),
(P<0.05)] and AT [HR: 0.59 (0.45-0.76), (P=0.0003)] were predictors of reduced
postoperative survival following elective EVAR whereas gender [HR: 0.75
(0.4-0.1.4), P=0.37)], AAA diameter [HR: 0.95 (0.77-0.1.16), (P=0.6)], AAA
morphology [HR: 1.23 (0.68-1.76), (P=0.95)] were not.
CONCLUSIONS: Anaerobic threshold is an independent predictor of prolonged
survival following elective EVAR and can be used to identify patients who receive
most benefit from elective EVAR.

Workload-indexed blood pressure response is superior to peak systolic blood pressure in predicting all-cause mortality

Kristofer Hedman, Nicholas Cauwenberghs,
Jeffrey W Christle, Tatiana Kuznetsova, Francois Haddad,
Jonathan Myers

European Journal of Preventive Cardiology 0(00) 1–10

Aims: The association between peak systolic blood pressure (SBP) during exercise testing and outcome remains
controversial, possibly due to the confounding effect of external workload (metabolic equivalents of task (METs)) on
peak SBP as well as on survival. Indexing the increase in SBP to the increase in workload (SBP/MET-slope) could provide a more clinically relevant measure of the SBP response to exercise.We aimed to characterize the SBP/MET-slope in a large cohort referred for clinical exercise testing and to determine its relation to all-cause mortality.
Methods and results: Survival status for male Veterans who underwent a maximal treadmill exercise test between the years 1987 and 2007 were retrieved in 2018. We defined a subgroup of non-smoking 10-year survivors with fewer risk factors as a lower-risk reference group. Survival analyses for all-cause mortality were performed using Kaplan–Meier curves and Cox proportional hazard ratios (HRs (95% confidence interval)) adjusted for baseline age, test year, cardiovascular risk factors, medications and comorbidities. A total of 7542 subjects were followed over 18.4 (interquartile range 16.3) years. In lower-risk subjects (n¼709), the median (95th percentile) of the SBP/MET-slope was 4.9 (10.0) mmHg/MET. Lower peak SBP (<210 mmHg) and higher SBP/MET-slope (>10 mmHg/MET) were both associated with 20% higher mortality (adjusted HRs 1.20 (1.08–1.32) and 1.20 (1.10–1.31), respectively). In subjects with high fitness, a SBP/MET-slope>6.2 mmHg/MET was associated with a 27% higher risk of mortality (adjusted HR 1.27 (1.12–1.45)).
Conclusion: In contrast to peak SBP, having a higher SBP/MET-slope was associated with increased risk of mortality.
This simple, novel metric can be considered in clinical exercise testing reports.

Heart rate recovery and morbidity after noncardiac surgery: Planned secondary analysis of two prospective, multi-centre, blinded observational studies.

Ackland GL; Abbott TEF; Minto G; Owen T; Prabhu P; May SM; Reynolds JA; Cuthbertson BH; Wijesundera D; Pearse RM;

Plos One [PLoS One] 2019 Aug 21; Vol. 14 (8), pp. e0221277. Date of Electronic Publication: 20190821 (Print Publication: 2019).

Background: Impaired cardiac vagal function, quantified preoperatively as slower heart rate recovery (HRR) after exercise, is independently associated with perioperative myocardial injury. Parasympathetic (vagal) dysfunction may also promote (extra-cardiac) multi-organ dysfunction, although perioperative data are lacking. Assuming that cardiac vagal activity, and therefore heart rate recovery response, is a marker of brainstem parasympathetic dysfunction, we hypothesized that impaired HRR would be associated with a higher incidence of morbidity after noncardiac surgery.
Methods: In two prospective, blinded, observational cohort studies, we established the definition of impaired vagal function in terms of the HRR threshold that is associated with perioperative myocardial injury (HRR ≤ 12 beats min-1 (bpm), 60 seconds after cessation of cardiopulmonary exercise testing. The primary outcome of this secondary analysis was all-cause morbidity three and five days after surgery, defined using the Post-Operative Morbidity Survey. Secondary outcomes of this analysis were type of morbidity and time to become morbidity-free. Logistic regression and Cox regression tested for the association between HRR and morbidity. Results are presented as odds/hazard ratios [OR or HR; (95% confidence intervals).
Results: 882/1941 (45.4%) patients had HRR≤12bpm. All-cause morbidity within 5 days of surgery was more common in 585/822 (71.2%) patients with HRR≤12bpm, compared to 718/1119 (64.2%) patients with HRR>12bpm (OR:1.38 (1.14-1.67); p = 0.001). HRR≤12bpm was associated with more frequent episodes of pulmonary (OR:1.31 (1.05-1.62);p = 0.02)), infective (OR:1.38 (1.10-1.72); p = 0.006), renal (OR:1.91 (1.30-2.79); p = 0.02)), cardiovascular (OR:1.39 (1.15-1.69); p<0.001)), neurological (OR:1.73 (1.11-2.70); p = 0.02)) and pain morbidity (OR:1.38 (1.14-1.68); p = 0.001) within 5 days of surgery.
Conclusions: Multi-organ dysfunction is more common in surgical patients with cardiac vagal dysfunction, defined as HRR ≤ 12 bpm after preoperative cardiopulmonary exercise testing.

Cardiopulmonary Exercise Testing Following Open Repair for a Proximal Thoracic Aortic Aneurysm or Dissection.

Hornsby WE; Departments of Internal Medicine, Division of Cardiovascular Medicine (Drs Hornsby, Saberi, Brook, Willer, Eagle, and Rubenfire and Ms Fink) and Cardiac Surgery (Drs Wu, Patel, and Yang), University of Michigan, Michigan Medicine, Ann Arbor; Creighton University School of Medicine, Omaha, Nebraska (Ms Norton); Department of Kinesiology, University of Windsor, Windsor, Ontario, Canada (Dr McGowan); Department of Medicine, Memorial Sloan Kettering Cancer Center, New York City, New York (Dr Jones); Departments of Computational Medicine and Bioinformatics and Human Genetics, University of Michigan, Ann Arbor (Dr Willer); and Department of Cardiovascular Diseases, John Ochsner Heart and Vascular Institute, Ochsner Clinical School-The University of Queensland School of Medicine, New Orleans, Louisiana (Dr Lavie).

Journal Of Cardiopulmonary Rehabilitation And Prevention [J Cardiopulm Rehabil Prev] 2019 Aug 29. Date of Electronic Publication: 2019 Aug 29.

Purpose: There are limited data on cardiopulmonary exercise testing (CPX) and cardiorespiratory fitness (CRF), following open repair for a proximal thoracic aortic aneurysm or dissection. The aim was to evaluate serious adverse events, abnormal CPX event rate, CRF (peak oxygen uptake, Vo2peak), and blood pressure.
Methods: Patients were retrospectively identified from cardiac rehabilitation participation or prospectively enrolled in a research study and grouped by phenotype: (1) bicuspid aortic valve/thoracic aortic aneurysm, (2) tricuspid aortic valve/thoracic aortic aneurysm, and (3) acute type A aortic dissection.
Results: Patients (n = 128) completed a CPX a median of 2.9 mo (interquartile range: 1.8, 3.5) following repair. No serious adverse events were reported, although 3 abnormal exercise tests (2% event rate) were observed. Eighty-one percent of CPX studies were considered peak effort (defined as respiratory exchange ratio of ≥1.05). Median measured Vo2peak was <36% predicted normative values (19.2 mL·kgmin vs 29.3 mL·kg·min, P < .0001); the most marked impairment in Vo2peak was observed in the acute type A aortic dissection group (<40% normative values), which was significantly different from other groups (P < .05). Peak exercise systolic and diastolic blood pressures were 160 mm Hg (144, 172) and 70 mm Hg (62, 80), with no differences noted between groups.
Conclusions: We observed no serious adverse events with an abnormal CPX event rate of only 2% 3 mo following repair for a proximal thoracic aortic aneurysm or dissection. Vo2peak was reduced among all patient groups, especially the acute type A aortic dissection group, which may be clinically significant, given the well-established prognostic importance of reduced cardiorespiratory fitness.

Acquired loss of cardiac vagal activity is associated with myocardial injury in patients undergoing noncardiac surgery: prospective observational mechanistic cohort study.

May SM; Reyes A; Martir G; Reynolds J; Paredes LG; Karmali S; Stephens RCM; Brealey D; Ackland GL;

British Journal Of Anaesthesia [Br J Anaesth] 2019 Sep 03. Date of Electronic Publication: 2019 Sep 03.

Background: Myocardial injury is more frequent after noncardiac surgery in patients with preoperative cardiac vagal dysfunction, as quantified by delayed heart rate (HR) recovery after cessation of cardiopulmonary exercise testing. We hypothesised that serial and dynamic measures of cardiac vagal activity are also associated with myocardial injury after noncardiac surgery.
Methods: Serial autonomic measurements were made before and after surgery in patients undergoing elective noncardiac surgery. Cardiac vagal activity was quantified by HR variability and HR recovery after orthostatic challenge (supine to sitting). Revised cardiac risk index (RCRI) was calculated for each patient. The primary outcome was myocardial injury (high-sensitivity troponin ≥15 ng L-1) within 48 h of surgery, masked to investigators. The exposure of interest was cardiac vagal activity (high-frequency power spectral analysis [HFLn]) and HR recovery 90 s from peak HR after the orthostatic challenge.
Results: Myocardial injury occurred in 48/189 (25%) patients, in whom 41/48 (85%) RCRI was <2. In patients with myocardial injury, vagal activity (HFLn) declined from 5.15 (95% confidence interval [CI]: 4.58-5.72) before surgery to 4.33 (95% CI: 3.76-4.90; P<0.001) 24 h after surgery. In patients who remained free of myocardial injury, HFLn did not change (4.95 [95% CI: 4.64-5.26] before surgery vs 4.76 [95% CI: 4.44-5.08] after surgery). Before and after surgery, the orthostatic HR recovery was slower in patients with myocardial injury (5 beats min-1 [95% CI: 3-7]), compared with HR recovery in patients who remained free of myocardial injury (10 beats min-1 [95% CI: 7-12]; P=0.02).
Conclusions: Serial HR measures indicating loss of cardiac vagal activity are associated with perioperative myocardial injury in lower-risk patients undergoing noncardiac surgery.

Influence of circadian blood pressure patterns and cardiopulmonary functional capacity in hypertensive patients.

Tadic M; Cuspidi C; Suzic-Lazic J; Andric A; Sala C; Santoro C; Iracek O; Celic V;

Journal Of Clinical Hypertension (Greenwich, Conn.) [J Clin Hypertens (Greenwich)] 2019 Aug 26. Date of Electronic Publication: 2019 Aug 26.

We sought to assess functional capacity in recently diagnosed untreated hypertensive patients with different 24-hour blood pressure (BP) patterns (dipping, non-dipping, extreme dipping, and reverse dipping). This cross-sectional study involved 164 untreated hypertensive patients who underwent 24-hour ambulatory BP monitoring and cardiopulmonary exercise testing. Our findings showed that 24-hour and daytime BP values did not differ between four groups. Nighttime BP significantly and gradually increased from extreme dippers to reverse dippers. There was no significant difference in BPs at baseline and at the peak of exercise among four observed groups. Peak oxygen consumption (peak VO2) was significantly lower in reverse dippers than in dippers and extreme dippers. Heart rate recovery was significantly lower among reverse dippers than in dippers and extreme dippers. Ventilation/carbon dioxide slope (VE/VCO2) was significantly higher in reverse dippers and non-dippers in comparison with dippers and extreme dippers. Non-dipping BP pattern (non-dippers and reverse dippers together) was independently and negatively associated lower heart rate recovery in the first minute and peak VO2. Reverse dipping BP pattern was independently associated not only with heart rate recovery in the first minute and peak VO2, but also with VE/VCO2. In conclusion, untreated hypertensive patients with reverse dipping BP patterns showed significantly worse functional capacity than those with dipping and extreme dipping BP patterns. Circadian BP rhythm is related with functional capacity and should be taken into account in the risk assessment of hypertensive patients.

The RESTORE Randomized Controlled Trial: Impact of a Multidisciplinary Rehabilitative Program on Cardiorespiratory Fitness in Esophagogastric cancer Survivorship.

O’Neill LM; Guinan E; Doyle SL; Bennett AE; Murphy C; Elliott JA;
O’Sullivan J; Reynolds JV; Hussey J.

Annals of Surgery. 268(5):747-755, 2018 11.

OBJECTIVE: The Rehabilitation Strategies in Esophagogastric cancer
(RESTORE) randomized controlled trial evaluated the efficacy of a 12-week
multidisciplinary program to increase the cardiorespiratory fitness and
health-related quality of life (HRQOL) of esophagogastric cancer
survivors.

BACKGROUND: Patients following treatment for esophagogastric cancer are
at risk of physical deconditioning, nutritional compromise, and
sarcopenia. Accordingly, compelling rationale exists to target these
impairments in recovery.

METHODS: Disease-free patients treated for esophagogastric cancer were
randomized to either usual care or the 12-week RESTORE program (exercise
training, dietary counseling, and multidisciplinary education). The
primary outcome was cardiopulmonary exercise testing (VO2peak). Secondary
outcomes included body composition (bioimpedance analysis), and HRQOL
(EORTC-QLQ-C30). Outcomes were assessed at baseline (T0), postintervention
(T1), and at 3-month follow-up (T2).

RESULTS: Twenty-two participants were randomized to the control group
[mean (standard deviation) age 64.14 (10.46) yr, body mass index 25.67
(4.83) kg/m, time postsurgery 33.68 (19.56) mo], and 21 to the
intervention group [age 67.19(7.49) yr, body mass index 25.69(4.02) kg/m,
time postsurgery 23.52(15.23) mo]. Mean adherence to prescribed exercise
sessions were 94(12)% (supervised) and 78(27)% (unsupervised). Correcting
for baseline VO2peak, the intervention arm had significantly higher
VO2peak at both T1, 22.20 (4.35) versus 21.41 (4.49) mL . min . kg, P <
0.001, and T2, 21.75 (4.27) versus 20.74 (4.65) mL . min . kg, P = 0.001,
compared with the control group. Correcting for baseline values, no
changes in body composition or HRQOL were observed.

CONCLUSIONS: The RESTORE program significantly improved cardiorespiratory
fitness of disease-free patients after esophagogastric cancer surgery,
without compromise to body composition. This randomized controlled trial
provides proof of principle for rehabilitation programs in esophagogastric
cancer.