Shock Wave Therapy: Fast cure for calcified blockages in arteries of heart

Kolkata: Heart disease patients often have tight blockages, caused by a deposit of soft or fibrous material, according to Dr. Anil Mishra, Medical Director & Senior Consultant Interventional Cardiologist - Cardiology Department – BMB - CK Birla Hospitals.

He said over a period of time calcium deposits in these blockages, eventually making some of them very hard and calcified. It becomes challenging for doctors to open these hard blockages with angioplasty due to the presence of excessive calcium.

Coronary calcium deposits hinder successful angioplasty and stenting due to the difficult passage of balloons and stent through the calcified lesion, coating of drug getting separated from the stent, inadequate expansion of the stent, and increased clot formation within the stent, all leading to worse clinical outcomes, Dr Mishra said.

Earlier, high-pressure balloons were used to crack these calcium deposits. But, unfortunately, the application of these balloons fails a lot of times, because the hard dense calcified lesion does not break easily and instead the opposing normal wall may expand and tear. Some of them could be subjected to high-speed drilling inside the calcified arteries with Rotational or Orbital atherectomy, he said.

But these are relatively complex procedures, for which a lot of interventional cardiologists are not trained and the procedure itself has its limitations and is associated with significant complication rates making it not such a lucrative option. Earlier the only option remaining for such patients was to undergo a bypass surgery, which is not a recommended treatment procedure for elderly people who are around 80 years of age and more, Dr. Mishra said.

Gradually with time, new techniques developed to overcome this growing concern but each of them had its own limitation and drawbacks. Today, in medical science, doctors are preferring to use the latest technique called shock boom therapy or Shockwave therapy or Intra Vascular Lithotripsy (IVL). It generates very high-pressure acoustic waves, which go from the balloon into the artery and this shock wave helps to crack the hard calcium deposits present inside the arterial wall. The advantage of this therapy is its simple usage without much of complication because there are no rotating high-speed drills inside that require special skills and conditions to pass, he said.

Dr Mishra said the shock wave therapy not only cracks the superficial layer but also goes deeper and cracks the deeper-located calcium as well, which none of the other techniques does. The dilating balloon used in this therapy is unique. Normal balloons cannot deliver the sonic pressure wave impulse needed for the purpose, which these shockwave balloons do by delivering the shock wave; because it is connected to equipment outside which delivers the energy required to develop the sonic pressure wave. This eventually helps the experts who are already carrying out angioplasty treatments, to carry out the technique without much extra effort or new learning.

With this method, the troublesome calcium is broken up or fractured using sonic pressure wave pulses. After this, a stent can be implanted more securely and completely to return the artery to its regular diameter. It is crucial to note that the broken calcium does not flow calcium particles downstream, which would clog up smaller branch vessels, but rather remains within the blood channel walls. This greatly increases the blood vessel's flexibility or compliances, enabling complete balloon inflation and stent deployment, he said.

Dr Mishra said the success rate of this treatment is high and strongly recommended by the medical experts. The hard solidified calcium can be cracked very easily by giving multiple impulses with an increase in the number of impulses. Patients within the age group of 20 to 50 years, can go up to 80 pulses to crack this calcium and it is controllable. The most significant part of this therapy is that it is using skills that the doctors are practicing on a daily basis. So every interventionist is used to it.

A doctor can perform and use this therapy to crack the calcium, and once the calcium is cracked, it is like any other lesion. This can be opened with this balloon system and the stents can be deployed easily. It uses just a normal coronary wire, which people are using all the time during a normal angioplasty, and also the calcium does not flow distally. Hence, there is no formation of clogging. Therefore, this has come as a boon for elderly and sick patients, who often have hard calcified blockages, where doctors do not want to take any chance at all and manages to get good clinical outcomes, he added. (UNI)