When V.S. Prasad, 58, lost consciousness for about half a minute in his bathroom last September, none of the doctors he went to initially could fathom why. They thought it was a case of syncope simply temporary loss of consciousness. All the usual tests failed to give any indicationsEven the 24-hour Holter monitoring(an ambulatory electrocardiography device for monitoring the heartbeat round the clock) failed to indicate any underlying heart disorder. The Tilt test (to detect syncope of neurological origin), too, was negative because of which the neurologist ruled out epilepsy,â€ says Arunangshu Ganguly, consultant interventional cardiologist at the Apollo Gleneagles Hospital, Calcutta.
Prasad’s case is not uncommon; cardiologists worldwide are often faced with such tricky situations. Dr Emilio Vanoli, associate professor at the Dipartimento di Cardiologia Policlinico of Monza, Italy, says: Syncope is a symptom that a doctor needs to interpret. Unfortunately, in more than 40 per cent of cases, it goes unregistered.â€ Lack of awareness â€” even among doctors â€” makes things difficult, he adds. Patients who complain of fainting spells are often treated as epileptics and the cardiac problem, if any, goes undetected. Similarly, epileptics are sometimes wrongly implanted with pacemakers.
Prasad was, however, more fortunate. Says Dr Ganguly: â€œI suspected some electrical problem in his heart. But none of the tests backed my intuition. Then I advised him to get an Insertable Loop Recorder (ILR) implanted. The device records the heartâ€™s functioning, providing evidence of what goes wrong during a fainting spell.â€
So when Prasad fainted again in December, he pressed the activator button on regaining consciousness. This, to store data about how his heart had behaved during the episode.
When Dr Ganguly analysed the data, he found that Prasadâ€™s heart had stopped beating for nearly 20 seconds. The doctor then concluded that Prasad was suffering from an abnormally low heart beat rate â€” less than 60 beats a minute is a cause for worry â€” and needed a pacemaker.
Launched in India in October 2007, the ILR has been on the US market for some years now. It costs around Rs 35,000 to get the thumb-sized device inserted through a non-invasive procedure under local anaesthesia. It has a battery life of 14 months, during which it can continuously record the userâ€™s heart beat.
The ILR promises to be of great use to many. â€œAbout 1.5 million people worldwide suffer from unexplained syncope. In almost 10 per cent of cases syncope has a cardiac cause, in 50 per cent a non-cardiac cause, and in the remaining 40 per cent of cases the cause remains unknown. The recorder is of great help as the fainting occurs suddenly and for a very brief duration. Moreover, there is no definite pattern of repetition, which makes documentation very difficult. We cannot perform an electrocardiograph (ECG) right then and the ECGs before and after are usually normal,â€ explains Dr Vanoli.
With the number of patients complaining of unexplained loss of consciousness increasing, unfortunately, there are instances where pacemakers are implanted without proper documentation of the cause, says Dr Ganguly. Not all cases of loss of consciousness are due to cardiological reasons; neurological, metabolic and other factors too could be at play.
The heart, explains the doctor, is an electromechanical pump which uses its muscles to continuously pump blood to the body system. The valves in it ensure a uni-directional blood flow. A mechanical failure of the organ doesnâ€™t lead to syncope except when there is a critical obstruction in the outflow valve or when there is an uncoordinated contraction of the heart muscles. All other causes of loss of consciousness attributed to a cardiological reason are due to a power failure in the electrical supply to the heart. This electrical supply originates in a generator (Sinus node) and is carried through a nerve to a distribution box (AV node) from where it reaches the heart by means of three nerves (one right bundle and two left bundles). Now when the generator or distribution point or any of the wires becomes incapable of providing uninterrupted power flow to the heart, the heart stops functioning and the brain â€” on not getting its blood supply â€” switches off, and the person faints. A stoppage of more than three seconds is fatal. And that is where you need an inverter to back you up, which is a pacemaker.
The ILR has helped us provide evidence-based treatment rather than fall back on presumptive management,â€ says Dr Ganguly. However, the cost could pose a problem for some, he feels.
Nonetheless, it comes as a huge relief to many people, sparing them the travails of presumptive management of their disease.
Sources: The Telegraph (Kolkata, India)