Editor's Note: This is Part 1 of a two-part series. Look for Part 2 in the March/April issue of Cardiovascular Business.
Recent studies suggest the staggering clinical and economic costs of critical limb ischemia can be reduced by utilizing newer treatment technologies
At the 2008 New Cardiovascular Horizons conference held in New Orleans, we created several visionary sessions titled Ã?Â¢??Treating the Infrapops Like the LADÃ?Â¢?? and Ã?Â¢??Treating PAD Like CAD.Ã?Â¢?? We designed these sessions to focus on the emerging interventional strategies and technologies to treat peripheral arterial disease (PAD) and, especially, critical limb ischemia (CLI), the end-stage of lower extremity PAD.
The costs in morbidity, mortality and dollars are astonishing regarding CLI. In the last two decades, the amputation rate has increased from 19 to 30 per 100,000 persons, with diabetics most at risk. Annual costs of treating CLI in the U.S. could top $20 billion. Follow-up, long-term care and treatment for one homebound amputee is about $49,000 per year compared with $600 per year after limb salvage. A 25 percent reduction of amputations could save more than $3 billion yearly in U.S. healthcare costs. These significant clinical and economic costs are staggering, especially with multiple published experiences appearing over the last three to four years reporting 85 percent to 95 percent limb salvage rates at 12 and 24 months utilizing contemporary peripheral vascular interventional (PVI) technologies.
I believe it is time we Ã?Â¢??treat PAD like CADÃ?Â¢?? and Ã?Â¢??treat infrapops like the LADÃ?Â¢?? with both refined PVI technologies and strategies that will indeed improve outcomes. I will review some of the emerging PVI strategies and technologies I have found clinically promising and have the potential to improve outcomes, especially in CLI.
Vessel imaging and sizing
Multidetector CT angiography (CTA) has been revolutionary in our PVI practice, not only in diagnosing but also in the overall interventional management of the PAD patient. We have found that CTA helps with accurate diagnosis, safer access site identification/management, procedural and device choice planning, as well as understanding vessel morphology and size. It also helps to lessen overall case time, as well as fluoroscopy time and contrast use. CTA identifies unknown anatomic challenges (tortuosity, ulcerative plaques, thrombus, etc.), facilitates PVI follow-up and potentially decreases vascular access complications.
For these reasons, peripheral CTA has totally replaced traditional diagnostic catheter peripheral angiography in our practice and most PVIs today are preceded by CTA. This strategy has optimized preprocedural planning, periprocedural case execution and improved our overall PVI outcomes.
Optimal vessel sizing is a prerequisite for percutaneous coronary intervention (PCI) and minimal lumen diameters are associated with improved short and long-term PCI outcomes. Intravascular ultrasound (IVUS) during PCI is commonplace, reimbursed and associated with improved PCI outcomes. Minimal lumen diameters are rarely mentioned during PVI and peripheral vascular IVUS is not reimbursed, therefore rarely used during PVIs. Little attention is given to precise/optimal vessel sizing during PVI, especially when treating infrapopliteal artery disease. Precise infrapopliteal artery sizing is complex, challenging and, unfortunately, Ã?Â¢??guess workÃ?Â¢?? is often used in PVI device decision-making, certainly much more so than during PCI. It only stands to reason that if we had a simple, cost-effective, accurate technology to precisely size infrapopliteal arteries, outcomes would similarly improve as PCI outcomes have. This is especially important now that we have small profile PVI technologies and dedicated infrapopliteal stents.
As a peripheral IVUS equivalent, we have utilized the Metricath Libra balloon (Neovasc) as a vessel-sizing balloon to precisely measure vessels, especially infrapopliteal arteries, to the hundredth millimeter. The Libra balloon inflates to 1/3 atm and uses a small computerized console to simply and quickly inflate in the reference vessel of interest and calculate the diameter of the vessel. We recently reported our experience in approximately 100 infrapopliteal arteries where about