Author + information
- Received October 26, 2016
- Revision received November 28, 2016
- Accepted November 30, 2016
- Published online February 6, 2017.
- Kalpa De Silva, MBBS, PhD,
- James Roy, MD,
- Ian Webb, MA, PhD,
- Rafal Dworakowski, MD, PhD,
- Narbeh Melikian, BSc, MD,
- Jonathan Byrne, MBBS, PhD,
- Philip MacCarthy, BSc, MBBS, PhD and
- Jonathan Hill, MA∗ ()
- ↵∗Address for correspondence:
Dr. Jonathan Hill, King’s College Hospital, Denmark Hill, London SE5 9RS, United Kingdom.
A 69-year-old man with established coronary artery disease and left ventricular dysfunction (ejection fraction, 40%) with typical Canadian Cardiovascular Society class III angina underwent percutaneous coronary intervention (PCI) for severe diffuse calcific disease in the right coronary artery (Figure 1). The vessel was prepared with 2.5-mm and 3.0-mm balloon pre-dilation. However, despite the use of 3.0-mm noncompliant balloon, there was inadequate balloon expansion with a “dog-bone” appearance observed (Figure 2). The patient was readmitted for a further attempt at PCI with adjunctive lithoplasty for calcium debulking. A 3.5 × 12 mm Lithoplasty balloon (Shockwave Medical, Fremont, California) was the initial and only balloon used to pre-dilate and treat the entire length of disease. Briefly, the Lithoplasty technique involves inflating the balloon to low pressure (4 atm) with 8 pulses of ultrasound energy of 10 s delivered per balloon. A degree of balloon deformation was observed secondary to a region of lesion constriction, at the nominal pressure of 4 atm, the Lithoplasty was initiated, with the balloon seen to inflate fully at this low pressure. The balloon is then inflated to 6 atm for 15 to 20 s after each pulse to maximize balloon expansion and aid removal of debris. Lithoplasty preferentially allows calcium modification without affecting the endovascular soft tissue, and subsequently aids stent delivery and optimization. Optical coherence tomography performed pre-lithoplasty and post-lithoplasty showed the “calcium cracking” effect of the technique (Figure 3, Online Video 1). The segment of disease was then treated with a 3.5 × 22 and 4.0 × 16 mm drug-eluting stent with a good OCT (Figure 4, Online Video 2) and angiographic (Figure 5) result.
Calcific coronary disease remains an important cause of stent under-expansion and represents a nidus for stent thrombosis. Revascularization undertaken in those >75 years, a cohort with increased coronary calcification, now accounts for 25% to 30% of all PCI procedures (1). Current techniques to modify calcific stenoses include standard or high-pressure noncompliant balloons, cutting/scoring balloons, or rotational atherectomy. High-pressure balloon treatment may lead to localized wall injury, which may provide a vascular substrate for restenosis, with this and rotational atherectomy also increasing the risk of coronary perforation (0.7% with rotational atherectomy vs. 0.1% in standard procedures) (2). Lithoplasty may provide an adjunct to PCI that provides focal calcium modification with limited localized injury to the endovascular surface while aiding stent delivery and expansion.
For supplemental videos and their legends, please see the online version of this article.
All authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received October 26, 2016.
- Revision received November 28, 2016.
- Accepted November 30, 2016.
- American College of Cardiology Foundation
- Vandermolen S.,
- Abbott J.,
- De Silva K.
- Cohen B.M.,
- Weber V.J.,
- Reslman M.,
- Casale A.,
- Dorros G.