We performed a retrospective analysis of 858 patients with CHD who attended a CRP at Hospital de Santo António, Porto, after an acute coronary syndrome or elective percutaneous coronary intervention (PCI), between January 2008 and December 2012. Patients who attended at least 80% of the CRP sessions were included. A subgroup of 386 patients for whom data were available on exercise testing during the program was analyzed with regard to the parameters assessed by this exam.

The CRP at our center is coordinated by a cardiologist and a physiatrist, and also includes specialists in vascular surgery, psychiatry, urology and endocrinology, as well as physiotherapists, nutritionists, nurses and social workers. Patients are referred following hospitalization in a cardiology ward or from cardiology outpatient clinics.

The program is organized in separate, sequential phases in accordance with international guidelines.19 Phases I and II were included in this study.

Phase I begins during hospitalization, and includes educating patients about their disease and control of cardiovascular risk factors; they are also encouraged to regain mobility in the ward, depending on their clinical condition.

Phase II takes place in the Cardiovascular Prevention and Rehabilitation Unit of our center on an outpatient basis, beginning 1–2 weeks after hospital discharge. An initial clinical assessment is performed by the specialist in physical medicine and rehabilitation, focusing on the cardiopulmonary, musculoskeletal and neurological systems. Patients are then referred for laboratory tests aimed at guiding strategies to control cardiovascular risk factors and for exercise testing to stratify cardiac risk with a view to prescribing an exercise program in accordance with international guidelines.19 Patients can also be referred for consultations in vascular surgery, endocrinology, psychiatry, urology, smoking cessation and nutrition depending on clinical indications. This is followed by 8–12 weeks (depending on the patient's clinical situation and response) of health education sessions for the patient and their relatives and supervised exercise sessions. The latter are held in groups of nine patients, with continuous telemetry and heart rate (HR) monitoring, under the supervision of the cardiologist and/or physiatrist, in accordance with current guidelines.19 The exercise sessions are held twice weekly, each lasting approximately 60 minutes, and include a warm‐up period, aerobic training, strength training (using dumbbells, exercise balls and other strength training equipment), a cool‐down period and flexibility exercises. The aerobic component occupies most of the session (40 minutes), using a treadmill and arm and leg ergometers. The intensity of each exercise is determined on the basis of the patient's exercise HR calculated by the Karvonen formula19 (50–80% of HR reserve determined during exercise testing), complemented by the patient's rating of perceived exertion on the Borg scale.19,20 In addition, patients are encouraged to exercise during the rest of the week at the same level of intensity as that prescribed for the supervised sessions in terms of training HR and Borg scale and aimed at achieving the target values recommended in international guidelines for weekly energy expenditure. Patients are re‐assessed at the end of phase II through repeat laboratory tests and exercise testing.

Determination of metabolic profile included measurement of total cholesterol (TC), low density lipoprotein cholesterol (LDL‐C), high density lipoprotein cholesterol (HDL‐C) and triglycerides (TG), and body mass index (BMI) was calculated. In diabetic patients, fasting blood glucose and hemoglobin A1C (HbA1C) were also assessed. Laboratory tests were performed on blood samples collected after 12 hours’ fasting.

NT‐proBNP levels were measured.

Functional capacity was assessed based on metabolic equivalents (METs) obtained during exercise testing.

The following parameters from exercise testing were analyzed: resting HR, chronotropic index and HR recovery.

The chronotropic index was calculated using the following equation: [(peak exercise HR − resting HR)/(220‐age)‐resting HR] × 100, expressed as a percentage.

HR recovery was assessed as the difference between peak exercise HR and HR after one minute of the recovery period, expressed in beats per minute (bpm).

Qualitative variables were presented as percentages and compared by the chi‐square test, and quantitative variables as means ± standard deviation and compared by the Student's t test. Values of p<0.05 were considered statistically significant. The statistical analysis was performed using Stata® version 12.0.

The study population consisted of 858 patients, of whom 24% were women (Table 1). Most patients were referred to the CRP following a diagnosis of myocardial infarction (69% of women and 68% of men). Female patients were significantly older (62±11 years vs. 60±11 years, p=0.01) and presented a higher prevalence of cardiovascular risk factors, particularly hypertension (70% vs. 57%, p<0.001), dyslipidemia (83% vs. 72%, p=0.001) and diabetes (37% vs. 28%, p=0.04). There was a higher percentage of smokers among men (36% vs. 22%, p<0.001). The prevalence of overweight and obesity was similar in both sexes (68%). Women presented higher baseline NT‐proBNP (1050±1759 pg/ml vs. 660±881 pg/ml, p<0.001) and more frequently had left ventricular systolic dysfunction (40% vs. 28%, p=0.01).

As shown in Table 2, virtually all patients were medicated with dual antiplatelets, statins, beta‐blockers and ACE inhibitors or ARBs at the start of phase II. In our study population, the proportion of women under pharmacological therapy was similar to men for all drug classes.

Analysis of the subgroup of 386 patients with exercise test data in terms of the variables previously studied in the overall study population showed similar results (Tables 3 and 4). Changes in dosage of beta‐blockers in this subgroup during phase II of the program (0–3 months) were analyzed; no statistically significant differences were found between the sexes (an increase in 9±7% of women and in 9±6% of men, and a decrease in 1±0.8% of women and in 1±0.6% of men, p=0.62). The changes were made by the attending cardiologist in outpatient consultations. Beta‐blocker therapy was not begun in any patient during phase II of the CRP.

Both female and male patients showed a significant decrease in NT‐proBNP (from 660±881 pg/ml to 345±526 pg/ml in men and from 1050±1759 pg/ml to 466 ± 508 pg/ml in women, p<0.001) (Table 5). The degree of improvement in this marker of ventricular dysfunction was significantly greater in women (476±739 pg/ml vs. 318±621 pg/ml, p=0.02) (Table 6).

There was a significant improvement in functional capacity following phase II of the CRP in both men and women (from 9.1±2.2 METs to 10.6±2.1 METs in men and from 7.6±1.7 METs to 8.7±1.8 METs in women, p<0.001) that was similar for both sexes (Tables 7 and 8).

Female patients presented a significant improvement in heart rate recovery (from 20±9 bpm to 23±9 bpm, p=0.005), and resting HR showed a tendency to fall after the CRP (from 69±13 bpm to 66±10 bpm, p=0.08); there was a non‐significant increase in chronotropic indices (from 65±17% to 68±18%, p=0.40) (Table 7).

Male patients showed a significant improvement in all parameters: resting HR (from 63±12 bpm to 61±11 bpm, p=0.03), chronotropic index (from 69±18% to 75±18%, p<0.001) and HR recovery (from 23±9 bpm to 26±12 bpm, p<0.001) (Table 7).

However, comparison of the degree of change in resting HR and chronotropic index during the CRP revealed no significant differences between the sexes (Table 8).

The authors declare that no experiments were performed on humans or animals for this study.

The authors declare that they have followed the protocols of their work center on the publication of patient data and that all the patients included in the study received sufficient information and gave their written informed consent to participate in the study.

The authors declare that no patient data appear in this article.