Extreme cold wave hits region

Islamabad : Patients suffering from any of the 12 cardiovascular diseases are at higher risk of contracting serious and life threatening complications in extreme cold weather conditions while according to health experts, the extreme fall in mercury may increase the risk of incidence of the CVDs.

Various studies have revealed that the morbidity and mortality due to CVDs including deep venous thrombosis, pulmonary embolism, aortic dissection and rupture, stroke, intracerebral haemorrhage, hypertension, heart failure, angina pectoris, myocardial infarction, sudden cardiac death, ventricular arrhythmia and atrial fibrillation have higher rates during the colder months as compared to summer season.

A number of studies conducted all around the globe have also revealed that the highest incidence of CVDs occurs during the colder winter months and the phenomenon contributes to greater number of deaths due to the CVDs in winter.

Winter particularly the extreme cold weather conditions is the time for patients with CVDs and those at risk of CVDs to take extra care in diet and adopt a lifestyle that may reduce their risk of having complications, said Head of Cardiac Centre at Pakistan Institute of Medical Sciences Professor Dr Naeem Malik while talking to ‘The News’ on Saturday.

He added in winter, the chances of heart attack increase especially in late hours of night while the chances of complications also get higher among patients suffering from CVDs.

He said exposure to extreme cold causes peripheral vasoconstriction, the narrowing of blood vessels that may lead to pulmonary oedema as a consequence of left ventricular failure and may also cause abnormal clotting.

Studies reveal that variation in incidence of CVDs is associated with a number of risk factors including temperature, physical activity, air pollution, infections, and dietary habits however the risk can be minimised by following precautionary measures specifically in colder winter months.

According to Professor Malik, the risk factors like the seasonal variation in the plasma level of fibrinogen, cholesterol, hormones and vasoactive substance including vasopressin (AVP), norepinephrine (NE), epinephrine (E) and angiotensin II, aldosterone and catecholamine tends to rise in winter and may cause serious complications.

A number of studies on seasonal variation in heart failure (HF) hospitalization carried out in France, Spain, Japan, Scotland, Australia, Brazil, Argentina, Italy, Turkey, Nigeria, Canada, and USA have revealed that admissions increase during the winter season and show decline in summer season.

It is important that both systolic and diastolic mean blood pressures exhibit a seasonal peak during winter and trough in summer among adults, the elderly, and children. The extreme cold affects blood pressure of both the healthy and hypertensive people.

Professor Malik said the most critical time for heart patients is night and in winter, the night get longer and colder making it more serious for heart patients till 10 O’clock in the morning. “Most of the deaths related to heart disease are reported from late night till morning,” he added.

He, like other health experts in the twin cities of Islamabad and Rawalpindi said the patients suffering from CVDs must avoid exposure to extreme cold in winter as it affects the pumping power of the heart muscle in patients with symptomatic congestive heart failure.