There was a time , even cardiac catheterisation was contraindicated if the aortic valve is significantly calcified. LV angiogram was judiciously avoided in all such patients . Why ? A significant increase in disabling strokes were witnessed .Those were the time a sense of fear (common sense ?) prevailed . Every one was following this dictum with sanctity .
Now in 2010 .TAVI has arrived with great fanfare . We not only cross the calcific valve , we literally play a violent contact sport in the aortic root for over two hours with all sorts of pushes and passes on a fragile valve.And we are happy to claim that stroke rate is comparable to aortic valve surgery and TAVI is not-inferior to AVR in high risk surgeries .
How is this possible ? As the times changed ? Is it true , our stroke fears are just imaginations or have we lost our faculty of reasoning and sense ? (Will it be logical to fund a research if someone claims a surgical technique to replace aortic valve in a beating heart without aortic cross clamping !)
Data shows even if distal protection devices are used the stroke rates can reach to objectionable levels .It remained a mystery , at least to me how no body was questioning this ? I was happy to find this editorial in NEJM which just stopped short of banishing this modality in its current form.
http://www.nejm.org/doi/full/10.1056/NEJMe1103978
What price it asks ? and leaves the readers to guess the answer ? NEJM wants to be too decent and polite , but in science politeness is generally not required , as long as your observations are correct !
For all those enthusiastic interventional cardiologists here is a positive message .
Nothing comes easy in science.Great inventions do have problems initially . Without major hurdles there can be no progress ! It is because of you modern cardiology is making giant strides . Remember the early days of angioplasty , early days of pacemaker . But please realise the most important issue is , whatever we innovate or discover it should be shown superior to the best existing modality in all aspects(Technique, procedural complications, long term outcome ,costs, side effects etc ) .It is awful to note new drugs or devices are rarely compared with the best treatment that is currently available .
A new treatment that simply complements or proves non-inferiority can never be considered an invention. How can we portray radio frequency renal denervation ( a complex lab procedure ) for controlling blood pressure as a great innovation for man kind while we have so many drugs and modalities available at a fraction of the cost with little consequence .
Reference
http://www.escardio.org/congresses/esc-2009/news/Pages/Transcatheter-Aortic-Valve-Implantation.aspx
Dr.S.Venkatesan MD 