The number of patients worldwide with heart failure almost doubled between 1990 and 2017, a new study has revealed.

According to the findings, the number of patients with the heart condition rose from 33.5 million in 1990 to 64.3 million in 2017.

Heart failure occurs when the heart muscle is not able to pump blood around the body as well as it should because it is too weak or stiff to work properly. Symptoms can include shortness of breath when you are more active than usual or when you are at rest, fatigue, weakness, and swelling in your feet, ankles and legs.

Around 90,000 people in Ireland are affected.

Canadian researchers used data from the Global Burden of Disease study to look at heart failure between 1990 and 2017 in 195 countries and territories. The countries were divided into five groups depending on their development status - low, low-middle, middle, high-middle and high sustainable development index (SDI).

The study found that during the study period, the prevalence rate of heart failure decreased by just over 20% in high SDI countries. However prevalence increased in low, low-middle and middle SDI countries.

The researchers said the rising prevalence rate of heart these countries was "driven by a surge of risk factors such as hypertension (high blood pressure), diabetes mellitus, obesity, smoking, and other unhealthy lifestyles".

Almost half of the global increase in the number of heart failure patients during 1990 to 2017 occurred in China (30%) and India (17%).

"An interplay of factors such as population growth, unhealthy behaviours including smoking, and air pollution are likely explanations," commented Dr Nicola Bragazzi of York University in Toronto.

Ischaemic heart disease, hypertensive heart disease, and chronic obstructive pulmonary disease (COPD) were the top three causes of heart failure, the study noted. These conditions accounted for almost three-quarters of the prevalence rates.

"Our study challenges the common view that heart disease is fully under control. Heart failure is a global public health concern. Public health workers and policymakers can use the data provided in this study to design interventions to prevent and manage heart failure in their countries.

"In addition, educational campaigns are needed to increase awareness about the importance of adopting healthy lifestyles," Dr Bragazzi said.

Details of the findings are published in the European Journal of Preventive Cardiology.