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The Specialist Forum | Vol. 19 No. 4 May 2019 | 7

NEWS

The first Shockwave intravascular lithotripsy (IVL) procedure in Africa was performed at the Union Netcare Hospital in Alberton (Johannesburg) at the end of March. Both interventional cardiologists were impressed with the new system, which makes it possible to modify challenging calcified lesions without serious complications experienced with traditional devices.

Sonic waves disrupt and crack calcium

Case vignetteMA is a 79-year old male patient presenting with a non-ST-elevation myocardial infarction (NSTEMI).  NSTEMI typically presents as a pressure-like substernal pain, occurring at rest or with minimal exertion. The pain generally lasts more than 10 minutes and may radiate to either arm, the neck or the jaw. The pain may be associated with dyspnoea, nausea or vomiting, syncope, fatigue, or diaphoresis. Sudden onset of unexplained dyspnoea with or without associated symptoms is also a common presentation. An angiogram was done by the patient’s primary cardiologist. The angiogram revealed that the patient had calcified lesions in his major arteries. Calcified lesions can make coronary interventions more difficult and lead to complications during the procedure as well as escalated healthcare costs. Initial pharmacological treatment included anticoagulation therapy and nitrogen-infusion. The patient stabilised and his pain lessened. On angiogram he was found to have 90% occlusion of the circumflex coronary artery and a 70%-80% occlusion of the left anterior descending. The right coronary artery was chronically occluded. Due to his age and the presence of comorbidities, surgery was not a viable option for this patient. Available options were to either crack the calcium with angioplasty using a very high-pressure balloon, but due to the amount of calcium, the concern was that this would either not work or lead to a complication such as vessel rupture or perforation. De-bulking of the lesion with a rotablator was the other option. Once again due to the amount of calcium and especially because the calcium was deep and not superficial, this was not an ideal option.

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The Specialist Forum | Vol. 19 No. 48 | May 2019

NEWS

F ollowing the 90-minute procedure, Dr Chris Zambakides said the predictability of the system was hugely impressive. Dr Zambakides was assisted by Dr Jean-Paul Theron.

Sonic pressure wavesThe system makes use of localised pulsatile sonic pressure waves allowing interventionists to tackle even the most challenging calcified lesions.

The mechanism is leveraging electrohydraulic-generated lithotripsy to produce high-speed sonic pressure waves that pass through soft tissue to selectively disrupt calcium. The concept adopted is similar to urologic extracorporeal lithotripsy, but IVL differs by expressing a focal effect with ultra-high energy. IVL is designed specifically for vascular applications with the technology producing unfocused energy that creates a localised effect only within the vessel. 

ParagMed, a local company specialising in

interventional cardiology for over 20 years, is the sole distributor of the system in South Africa. Paragmed is currently in discussions with medical schemes about inclusion of the system in benefit packages. Currently approval is granted on a case-to-case basis, said Glenda Pakes, director of ParagMed.

To date, more than 1 000 procedures have been performed – predominantly in the United Kingdom, Europe and New Zealand. The system is currently undergoing regulatory approval in the United States. All procedures have been done in patients between the ages of 60 and 80 years with a success rate of 99%.

Safety and efficacyThe Disrupt Coronary Artery Disease (DISRUPT-CAD) prospective multi-centre, single-arm study, involving 60 patients with severely calcified lesions study, assessed the safety and performance of the Shockwave IVL system.

The primary safety endpoint was major adverse cardiac event (MACE) within 30 days defined as cardiac death, myocardial infarction (MI) or target vessel revascularisation (TVR). The primary performance endpoint was clinical success defined as residual stenosis (defined as stenosis <50% following stenting without in-hospital MACE.

The researchers found that shockwave IVL treatment was highly effective in facilitating the delivery of stents and reducing restenosis. Stent deployment was performed in 100% of the patients with reduction in residual stenosis to <50% in all patients despite more than 90% of patients having heavily calcified lesions. There were no major intra-procedural complications including perforation, embolisation, slow-flow or no reflow and a low MACE rate out to six months (8.5%).

In addition, consistent, reproducible luminal gain was also achieved. The clinical success rate was achieved in 95% of the patients limited only by 5% asymptomatic non-Q-wave MI. IVL catheter delivery and treatment at the target lesion was successful in 98.3% of the patients. The primary safety endpoint of 30-day MACE rates was achieved. There were no cardiac deaths, Q-wave MIs or target vessel revascularisations during this time period.

Patient selectionPatient selection is extremely important, stressed Dr Zambakides. The system is ideal for patients with heavily calcified lesions – especially deep calcium. He noted that the severity of calcification is not always obvious but may only be visible once you perform an angioplasty. In this instance, Dr Zambakides recommends that instead of persevering, rather switch to the Shockwave IVL procedure in these patients, which makes up about 5% of patients seen by cardiologists.

“It is often extremely difficult to achieve the high pressure needed to ‘crack’ calcified lesion with angioplasty, while rotablation is suitable for smaller vessels,” he added. He compared the new system with a drill that allows you to ‘hammer away’ at

Interventional cardiologists based at Netcare Union Hospital, Drs Chris Zambakides (right) and Jean-Paul Theron, performed the first Shockwave intravascular lithotripsy procedure in Africa.

Shockwave IVL is a novel device that delivers localised pulsatile sonic pressure waves, modifying calcified lesions in a safe and reproducible manner.

Minimize trauma to soft tissue by safely selecting and fracturing intimal and medial calcium

Optimize outcomes while reducing complications and cost escalation

Simple and intuitive system that makes complexcalcified procedures more predictable

SIMPLIFY PROCEDURES

OPTIMIZE OUTCOMES

MINIMIZE TRAUMA

Prior to use, please reference the Instructions for Use for more information on indications,

contraindications, warnings, precautions, and adverse events. www.shockwavemedical.com© 2019 Shockwave Medical, Inc. All Rights Reserved. IVL Overview | SPL 62444 Rev. A

Your Sound Calcium Strategy.

Learn more at ShockwaveIVL.com

MINIMIZE TRAUMA | OPTIMIZE OUTCOMES | SIMPLIFY PROCEDURES

Shockwave IVL proudly distributed in South Africa by Paragmed

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The Specialist Forum | Vol. 19 No. 410 | May 2019

NEWSthe calcium. The process weakens and cracks the calcium, allowing the balloon to expand and making placement of the stent easier and safer.

How does the system work?The Shockwave IVL system is unlike any other balloon devices that are used routinely during angioplasty procedures. It uses electronic energy from a portable generator which is delivered through a connector cable to a balloon catheter. Electricity travels from the generator to the balloon and creates a vapour or gas bubble that sends out sonic pressure waves via electrodes inside the balloon, which produce a spark and in so doing, produces and delivers shockwaves through the entire depth of the arterial wall. This can be as much as 40-50 atmospheric pressure (ATM). This in turn disrupts and modifies calcium through all the layers of the artery and not just in the superficial layer. Ten pulses are delivered at one second intervals per activation. Each balloon (12mm) can deliver up to 80 pulses.

The system comprises:

1 A compact, battery-powered generator

2 A simple and quick hand-held connector cable with a single therapy delivery button

3 An intuitive catheter, which houses an array of lithotripsy emitters enclosed in an integrated balloon.

The IVL catheter is delivered across a calcified lesion over a regular 0.014” wire and the integrated balloon is expanded to four ATM’s to facilitate efficient energy transfer. An electrical discharge from the emitters vaporises the fluid within the balloon, creating a rapidly expanding and collapsing bubble that generates sonic pressure waves.

The waves create a localised field effect, travelling through soft vascular tissue, selectively cracking intimal and medial calcium within the vessel wall. After calcium modification, the integrated balloon may subsequently be used to dilate the lesion at low pressure in order to maximise luminal gain.

Another benefit of this approach is soft tissue trauma is minimised by safely selecting and fracturing intimal and medial calcium. Conscious sedation can be used, and patient recovery is fast. As we were leaving the theatre, the patient piped up and said he was ready to go home.

For more information on the Shockwave IVL system, contact Glenda Pakes on (011) 476- 6790 or 082 321 0463. Alternatively send an email to: glenda@paragmed.co.za. SF

Dr Chris Zambakides explained that the Shockwave IVL system will help address the challenge of managing a subsection of heavily calcified vessels. Often such vessels cannot be successfully or safely treated without additional strategies, over and above conventional percutaneous transluminal coronary angioplasty. Shockwave IVL produces sonic waves which disrupts and cracks intimal and medial calcium without damaging the internal elastic lumina, making vessels more elastic to ensure more lumen gain and optimise stent deployment.