Stroke continues to be a leading cause of death and disability in the country. While significant advancement has been made in the treatment of stroke, there is a need for an in-depth study of causative factors to understand its root cause. Fifty per cent of strokes in those below 60 years is caused by an opening in the partition between the two upper chambers of the heart that failed to close fully after birth. This opening is referred to as patent foramen ovale (PFO). There is very little awareness about the treatment options for these patients. Advances in catheter-based therapy have paved a way for treating these patients more effectively and safely as compared to the more potent blood thinners, which were the only option.
PFO and its cause
Prior to birth, there is an opening in the heart partition, between the right and left upper chambers. This opening allows blood enriched with oxygen from mother’s placenta to bypass the baby’s lungs that do not function until birth. Once the child is born and the lungs become functional, a tissue flap closes the opening and within a few months is sealed completely. In about 25-30 per cent of babies, the foramen ovale tissue flap does not close completely. When the foramen ovale remains opens, it is called patent foramen ovale. Although PFO is common, in rare cases, it allows a blood clot to pass from the right side of your heart to the left side of your heart bypassing the lung filter, and then travel to the brain where it can block a blood vessel, resulting in a stroke. Therefore, the presence of a PFO is believed to be a factor that could lead to an ischemic stroke in the young.
How technology is coming to the rescue
Among the many treatment options available today, there are different kinds of occluders that can be placed in the heart to close the PFO using a minimally invasive catheter procedure. The procedure involves puncturing a vein in the groin and inserting a small catheter to guide the occluder into the heart. This occluder closes the opening in the heart. Once the device is placed across the PFO, the implanting cardiologist carefully studies its position using cardiac imaging tools. Once the cardiologist is satisfied with the position of the occluder, the device is released to remain permanently in the heart and all the catheters are removed to complete the procedure. After the procedure, the patients can return to normal activities in a couple of days.
PFO closure with a device has proven to reduce recurrence of strokes significantly in patients with PFO related stroke, especially in the younger population (< 60 years). It can also reduce the risk of bleeding associated with long-term use of blood thinners that have been used conventionally. Most people can take blood thinners for years without a risk. Since blood thinners help prevent blood clots, even tiny cuts or bruises will bleed a lot more when these drugs are consumed daily and therefore will necessitate change in lifestyle, like inability to participate in contact sports or undertake activities that have a potential to cause trauma or injury. The other disadvantage of this group of medicines is their interaction with certain food and with other medicines routinely used for cough, cold and fever. They also require regular blood monitoring. Stroke is becoming a major cause of death in low-income and middle-income countries like India. What we need today is a focus on early diagnosis, public awareness and capacity building at different levels of health care. It is important to live a healthy lifestyle comprising appropriate diet, regular physical activity, avoiding smoking, controlling blood pressure and diabetes, limiting or avoiding alcohol and modifying response to stress.
The writer is consultant interventional paediatric cardiologist, Madras Medical Mission, Chennai.