Occurrence of acute myocardial infarction in winter tourists: data from a retrospective questionnaire

Environmental Temperature, Other Climatic Variables, and Cardiometabolic Profile in Acute Myocardial Infarction

Objectives: To evaluate CV profiles, periprocedural complications, and in-hospital mortality in acute myocardial infarction (AMI) according to climate. Methods: Data from 2478 AMI patients (1779 men; mean age 67 ∓ 13 years; Pasquinucci Hospital ICU, Massa, Italy; 2007-2018) were retrospectively analyzed according to climate (LAMMA Consortium; Firenze, Italy) by using three approaches as follows: (1) annual warm (May-October) and cold (November-April) periods; (2) warm and cold extremes of the two periods; and (3) warm and cold extremes for each month of the two periods. Results: All approaches highlighted a higher percentage of AMI hospitalization for patients with adverse CV profiles in relation to low temperatures, or higher periprocedural complications and in-hospital deaths. In warmer times of the cold periods, there were fewer admissions of dyslipidemic patients. During warm periods, progressive heat anomalies were characterized by more smoker (approaches 2 and 3) and young AMI patient (approach 3) admissions, whereas cooler times (approach 3) evidenced a reduced hospitalization of diabetic and dyslipidemic patients. No significant effects were observed for the heat index and light circulation. Conclusions: Although largely overlapping, different approaches identify patient subgroups with different CV risk factors at higher AMI admission risk and adverse short-term outcomes. These data retain potential implications regarding pathophysiological mechanisms of AMI and its prevention.

Exercise in cold: Friend than foe to cardiovascular health

Exercise has been proven to benefit human health comprehensively regardless of the intensity, time, or environment. Recent studies have found that combined exercise with a cold environment displays a synergistical beneficial effect on cardiovascular system compared to exercise in thermoneutral environment. Cold environment leads to an increase in body heat loss, and has been considered a notorious factor for cardiovascular system. Exercise in cold increases the stress of cardiovascular system and risks of cardiovascular diseases, but increases the body tolerance to detrimental insults and benefits cardiovascular health. The biological effects and its underlying mechanisms of exercise in cold are complex and not well studied. Evidence has shown that exercise in cold exerts more noticeable effects on sympathetic nervous activation, bioenergetics, anti-oxidative capacity, and immune response compared to exercise in thermoneutral environment. It also increases the secretion of a series of exerkines, including irisin and fibroblast growth factor 21, which may contribute to the cardiovascular benefits induced by exercise in cold. Further well-designed studies are needed to advance the biological effects of exercise in cold. Understanding the mechanisms underlying the benefits of exercise in cold will help prescribe cold exercise to those who can benefit from it.

Cardiovascular effects and risks of recreational alpine skiing in the elderly

OBJECTIVES

Alpine skiing is one of the most popular recreational winter sports and attracts millions of tourists every year alone in the Alpine region. Several studies highlight the positive effects of alpine skiing as aerobic physical training and isometric muscle activity that is able to increase exercise capacity and reduce cardiovascular risk factors. However, a certain cardiovascular risk mainly related to an abrupt increase of myocardial oxygen consumption during skiing especially in otherwise sedentary subjects and effects of hypoxia in untrained patients have to be acknowledged.

DESIGN

In this article, we provide an up-to-date evaluation of risks and benefits of alpine skiing in relation of cardiovascular disease and elderly persons.

METHODS

Narrative Review.

RESULTS

In the first section, the current recommendations of physical activity and effects of alpine skiing - with particular attention to the elderly population - are described. In the second section, the present knowledge regarding cardiovascular risk and alpine skiing is summarized and possible pathophysiological mechanisms are highlighted. Finally, a summary regarding actual clinical recommendations is provided.

CONCLUSIONS

Alpine skiing may safely be recommended also to the elderly if certain precautions are applied, as the benefits outbalance the potential risks in most subjects.

Cardiovascular diseases, cold exposure and exercise

Both acute and prolonged cold exposure affect cardiovascular responses, which may be modified by an underlying cardiovascular disease. In addition, exercise in a cold environment increases cardiovascular strain further, but its effects among persons with cardiovascular diseases are not well known. Controlled studies employing whole-body or local cold exposure demonstrate comparable or augmented increase in cardiac workload, but aggravated cutaneous vasoconstriction in persons with mild hypertension. A strong sympathetic stimulation of a cold pressor test, increases cardiac workload in persons with coronary artery disease (CAD), but does not markedly differ from those with less severe disease or healthy. However, cold exposure reduces myocardial oxygen supply in CAD, which may lead to ischemia. Exercise in cold often augments cardiac workload in persons with CAD more than when performed in thermoneutral conditions. At the same time, reduced myocardial perfusion may lead to earlier ischemia, angina and impaired performance. Also having a heart failure deteriorates submaximal and maximal performance in the cold. Antianginal medication is beneficial in the cold in lowering blood pressure, but does not affect the magnitude of cold-related cardiovascular responses in hypertension. Similarly, the use of blood pressure lowering medication improves exercise performance in cold both among persons with CAD and heart failure. Both the acute and seasonal effects of cold and added with exercise may contribute to the higher morbidity and mortality of those with cardiovascular diseases. Yet, more controlled studies for understanding the pathophysiological mechanisms behind the adverse cold-related health effects are warranted.

Alpine Skiing as Winter-Time High-Intensity Training

INTRODUCTION

To counteract the winter activity deficit, we set out to analyze cardiorespiratory and metabolic responses of two high-intensity training (HIT) protocols during alpine skiing (AS), cross-country skiing (XCS), and indoor cycling (IC) and the effects of sex, age, and fitness level in this comparison.

METHODS

Nineteen healthy subjects (two age and fitness groups, both sexes) performed AS, XCS, and IC with measurements of oxygen uptake (V˙O2), energy expenditure (EE), HR, lactate, blood glucose and rate of perceived exertion, determined during 4 min of continuous HIT (HITc: 90% HRmax for XCS and IC or short turn skiing during AS) or 10-min intermittent HIT [HITint: 5 × 1 min high intensity (>90% HRmax or short turn skiing), 1 min active recovery].

RESULTS

During all three exercise modes and irrespective of HIT protocols, sex, age, and fitness, participants were able to reach exercise intensities >90% HRmax and >84% V˙O2max. In all exercise modes 10-min of HITint with a 10-min postexercise O2 consumption phase resulted in greater mean EE per minute compared to 4-min HITc with 10 min postexercise O2 consumption. When applying the same HIT loading and recovery pattern to all three exercise modes, EE during approximately 1:15 h of AS was equivalent to about 1:00 h of either XCS or IC.

CONCLUSIONS

Across all exercise modes and HIT protocols, high cardiorespiratory and metabolic responses were achieved regardless of age, sex, or fitness. EE during AS can be maximized by choosing the skiing mode "short turn skiing" in combination with an HITint to prolong the duration of continuous high-intensity loading during each descent. Therefore, all exercise modes and both HIT protocols are applicable and feasible in a broad spectrum of healthy subjects.

Foreign citizen mortality in Iceland January 2006 - December 2016

BACKGROUND

In recent years, tourism has become the number one account for foreign exchange income in Iceland, overtaking the fisheries industry and aluminium production. The rise of tourism has strongly affected Icelandic society in various sectors. With the increase of tourists visiting Iceland, the number of foreign citizens that died and were autopsied also rose.

METHOD

Data were collected from the Department of Forensic Pathology at Landspitali University Hospital in Reykjavik for the period January 2006 - December 2016.

RESULT

During this time there were 109 autopsies performed on foreign citizens of which 58 died from natural causes, 49 were injury deaths and in 2 cases no certain cause of death could be determined. Most represented were citizens from North America, United Kingdom and Germany (each 11%). The main causes of death were cardiovascular events (41%) followed by unintentional injuries (34%).

CONCLUSION

The research at hand shows the significant influence of tourism on Forensic Medicine and provides an update on deaths of overseas travellers. Furthermore this study points out variable risks of travel-related injuries and deaths in Iceland.

Coronary responses to cold air inhalation following afferent and efferent blockade

Cardiac ischemia and angina pectoris are commonly experienced during exertion in a cold environment. In the current study we tested the hypotheses that oropharyngeal afferent blockade (i.e., local anesthesia of the upper airway with lidocaine) as well as systemic β-adrenergic receptor blockade (i.e., intravenous propranolol) would improve the balance between myocardial oxygen supply and demand in response to the combined stimulus of cold air inhalation (-15 to -30°C) and isometric handgrip exercise (Cold + Grip). Young healthy subjects underwent Cold + Grip following lidocaine, propranolol, and control (no drug). Heart rate, blood pressure, and coronary blood flow velocity (CBV, from Doppler echocardiography) were continuously measured. Rate-pressure product (RPP) was calculated, and changes from baseline were compared between treatments. The change in RPP at the end of Cold + Grip was not different between lidocaine (2,441 ± 376) and control conditions (3,159 ± 626); CBV responses were also not different between treatments. With propranolol, heart rate (8 ± 1 vs. 14 ± 3 beats/min) and RPP responses to Cold + Grip were significantly attenuated. However, at peak exercise propranolol also resulted in a smaller ΔCBV (1.4 ± 0.8 vs. 5.3 ± 1.4 cm/s, P = 0.035), such that the relationship between coronary flow and cardiac metabolism was impaired under propranolol (0.43 ± 0.37 vs. 2.1 ± 0.63 arbitrary units). These data suggest that cold air breathing and isometric exercise significantly influence efferent control of coronary blood flow. Additionally, β-adrenergic vasodilation may play a significant role in coronary regulation during exercise.

Aortic dissection type A in alpine skiers

PATIENTS AND METHODS

140 patients with aortic dissection type A were admitted for cardiac surgery. Seventy-seven patients experienced their dissection in the winter season (from November to April). We analyzed cases of ascending aortic dissection associated with alpine skiing.

RESULTS

In 17 patients we found skiing-related aortic dissections. Skiers were taller (180 (172-200) cm versus 175 (157-191) cm, P = 0.008) and heavier (90 (68-125) kg versus 80 (45-110) kg, P = 0.002) than nonskiers. An extension of aortic dissection into the aortic arch, the descending thoracic aorta, and the abdominal aorta was found in 91%, 74%, and 69%, respectively, with no significant difference between skiers and nonskiers. Skiers experienced RCA ostium dissection requiring CABG in 17.6% while this was true for 5% of nonskiers (P = 0.086). Hospital mortality of skiers was 6% versus 13% in nonskiers (P = 0.399). The skiers live at an altitude of 170 (0-853) m.a.s.l. and experience their dissection at 1602 (1185-3105; P < 0.001) m.a.s.l. In 82% symptom start was during recreational skiing without any trauma.

CONCLUSION

Skiing associated aortic dissection type A is usually nontraumatic. The persons affected live at low altitudes and practice an outdoor sport at unusual high altitude at cold temperatures. Postoperative outcome is good.

Warm winter is associated with low incidence of ST elevation myocardial infarctions and less frequent acute coronary angiographies in an alpine country

BACKGROUND

Weather conditions influence symptoms in chronic stable coronary artery disease (CAD). Whether the ongoing climate change, with continuous and rapid temperature increases, also has an impact on the incidence and outcome of non-ST elevation (NSTEMI) and ST elevation (STEMI) myocardial infarctions referred for acute coronary angiography (CA) is less clear.

METHODS

According to weather data from the Institute of Meteorology and Geophysics, Innsbruck University, the 2005/2006 winter was very cold (CW) and the 2006/2007 winter extraordinarily warm (WW). As the overall invasive management of patients with acute coronary syndromes did not change substantially within these winters, we compared patients referred for acute CA suffering an acute STEMI or NSTEMI, their risk factors and in-hospital mortality rates between these two consecutive winters.

RESULTS

As expected, the average temperature was lower (- 1.6 vs. + 5.9°C; p < 0.001) and humidity was higher (82 vs. 79%; p < 0.012) in CW compared to WW, with no significant differences in other weather conditions (rainfall: 59 vs. 39 days; sunshine: 3.9 vs. 4.3 h/day; air pressure: 713.04 vs. 713.76 hPa). There were no differences in the number of overall CA (987 vs. 983) between these two winters, whereas the number of acute CA (12.9 vs. 10.4% of overall CA; p = 0.046) and the diagnosis of STEMI as an indication of acute CA (74.0% vs. 62.7%; p = 0.046) were higher in CW. Furthermore, patients in CW were younger (58.2 ± 12.4 vs. 61.7 ± 11.7 years; p < 0.03), had higher LDL cholesterol (134.8 ± 44.6 vs. 116.7 ± 36.0 mg/dl; p < 0.003) and were less frequently hypertensives (52.8 vs. 70.6%; p < 0.01). Other traditional risk factors were not different between WW and CW. In addition, there were no differences in in-hospital mortality rates in invasively diagnosed CAD, patients' nationalities (Austrians: 78.0 vs. 77.5%) and time from pain to arrival in the cath lab in STEMI patients (3.9 ± 3.5 vs. 3.8 ± 3.1 h).

CONCLUSION

The average temperature increase of 7.5°C from the cold to the warm winter was associated with a decrease in acute coronary angiographies, in particular due to a lower incidence of STEMI referred for primary percutaneous intervention.