Airway patency was explored in patients breathing spontaneously under deep halothane anaesthesia. Opening and closing of the airway was observed with a flexible bronchoscope looking proximally from the nasopharynx at the epiglottis and the tongue. With the occiput elevated at various angles the smallest angle of retroflexion of the neck necessary to open the airway was measured. The influence of artificial airways on this angle of retroflexion was measured. Cadaveric preparations of the upper airway were studied to assess the mechanisms involved in airway patency. The results indicate that the epiglottis and not the tongue is the main cause of obstruction of the upper airway. When methods are applied to displace the hyoid anteriorly, the airway will be cleared on most occasions.

Recently, high-intensity interval training (HIIT) has emerged as an alternative and/or complementary exercise modality to continuous aerobic exercise training (CAET) in CHD patients. However, the literature contains descriptions of many HIIT protocols with different stage durations, nature of recovery and intensities. In this review, we discuss the most recent forms of validated HIIT protocols in patients with coronary heart disease (CHD) and how to prescribe and use them during short- and long-term (phase II and III) cardiac rehabilitation programs. We also compare the superior and/or equivalent short- and long-term effects of HIIT versus CAET on aerobic fitness, cardiovascular function, and quality of life; their efficiency, safety, and tolerance; and exercise adherence. Short interval HIIT was found beneficial for CHD patients with lower aerobic fitness and would ideally be used in initiation and improvement stages. Medium and/or long interval HIIT protocols may be beneficial for CHD patients with higher aerobic fitness, and would be ideally used in the improvement and maintenance stages because of their high physiological stimulus. Finally, we propose progressive individualized models of HIIT programs (phase II to III) for patients with CHD and how to ideally use them according to the clinical status of patients and phase of the cardiac rehabilitation program.

We aimed to compare cardiopulmonary exercise test (CPET) parameters, cardiac adaptations and proportion of responders after different aerobic training programs amongst women and men with coronary heart disease (CHD). Patients with CHD were evaluated with a CPET and echocardiography before and after 3 month of aerobic exercise training. V̇O2 peak exercise training response was assessed according to the median V̇O2 peak change post vs. pre-training in the whole cohort (stratification non-/low-responders (NLRes) vs. high-responders) and normalized for lean body mass (LBM). Eighty three CHD patients were included (19 women, 64 men), (27 patients with interval, 19 with continuous and 37 with a combination). V̇O2 peak, peak work load normalized for LBM, pulmonary (i.e. ventilation and OUES) and O2 pulse were significantly lower in women vs. men.These parameters improved similarly with training in both sexes (p<0.05). There were no differences in the proportion of NLRes among women and men with CHD (7/19 or 37% vs. 35/64 or 55%, p=0.1719). Left ventricular ejection fraction and mean peak early diastolic mitral annulus velocity improved similarly with training in both sexes (p<0.05). Women and men with CHD have a similar exercise training response regarding key CPET, echocardiographic parameters. The proportion of responders is similar. ClinicalTrials.gov: NCT03414996, NCT02048696, NCT03443193 Novelty: Cardiopulmonary adaptations to exercise training is similar among CHD men and women Proportion of V̇O2 peak non-/low-/high-responders is similar in CHD men and women LV systolic (LVEF) and diastolic (e’) function improved similarly after exercise training in CHD men and women

Objective: To compare the effects of high-intensity interval training versus moderate-intensity continuous training on risk markers of arrhythmic death in patients who recently suffered from an acute coronary syndrome. Design: Double-blind (patient and evaluator) randomized controlled trial. Setting: Cardiovascular Prevention and Rehabilitation Centre (EPIC Centre) of the Montreal Heart Institute, Montreal, Canada. Subjects: A total of 43 patients were randomized following an acute coronary syndrome. Interventions: Patients were assigned to either high-intensity interval training (n = 18) or isocaloric moderate-intensity continuous training (n = 19), three times a week for a total of 36 sessions. Main measures: Heart rate recovery for 5 minutes, heart rate variability for 24 hours, occurrence of ventricular arrhythmias, and QT dispersion were measured before and after the 36 sessions of training. Results: Among the 43 patients randomized, 6 participants in the high-intensity interval training group stopped training for reasons unrelated to exercise training and were excluded from the analyses. Heart rate recovery improved solely in the high-intensity interval training group, particularly at the end of recovery period ( p < 0.05). There were no differences in heart rate variability, occurrence of ventricular arrhythmias, or QT dispersion parameters between the groups at study end. Conclusion: Despite the lack of power to detect any large difference between the two interventions with respect to risk markers of arrhythmic death, high-intensity interval training appears safe and may be more effective at improving heart rate recovery relative to moderate-intensity continuous training in our patients following acute coronary syndrome.