Contemporary Approach to Heavily Calcified Coronary Lesions

In-Stent Restenosis Overview: From Intravascular Imaging to Optimal Percutaneous Coronary Intervention Management

Despite ongoing progress in stent technology and deployment techniques, in-stent restenosis (ISR) still remains a major issue following percutaneous coronary intervention (PCI) and accounts for 10.6% of all interventions in the United States. With the continuous rise in ISR risk factors such as obesity and diabetes, along with an increase in the treatment of complex lesions with high-risk percutaneous coronary intervention (CHIP), a substantial growth in ISR burden is expected. This review aims to provide insight into the mechanisms, classification, and management of ISR, with a focus on exploring innovative approaches to tackle this complication comprehensively, along with a special section addressing the approach to complex calcified lesions.

Feasibility of in vitro calcification plaque disruption using ultrasound-induced microbubble inertial cavitation

Percutaneous transluminal coronary angioplasty (PTCA) is a clinical method in which plaque-narrowed arteries are widened by inflating an intravascular balloon catheter. However, PTCA remains challenging to apply in calcified plaques since the high pressure required for achieving a therapeutic outcome can result in balloon rupture, vessel rupture, and intimal dissection. To address the problem with PTCA, we hypothesized that a calcified plaque can be disrupted by microbubbles (MBs) inertial cavitation induced by ultrasound (US). This study proposed a columnar US transducer with a novel design to generate inertial cavitation at the lesion site. Experiments were carried out using tubular calcification phantom to mimic calcified plaques. After different parameters of US + MBs treatment (four types of MBs concentration, five types of cycle number, and three types of insonication duration; n = 4 in each group), inflation experiments were performed to examine the efficacy of cavitation for a clinically used balloon catheter. Finally, micro-CT was used to investigate changes in the internal structure of the tubular plaster phantoms. The inflation threshold of the untreated tubular plaster phantoms was > 11 atm, and this was significantly reduced to 7.4 ± 0.7 atm (p = 5.2E-08) using US-induced MBs inertial cavitation at a treatment duration of 20 min with an acoustic pressure of 214 kPa, an MBs concentration of 4.0 × 108 MBs/mL, a cycle number of 100 cycles, and a pulse repetition frequency of 100 Hz. Moreover, micro-CT revealed internal damage in the tubular calcification phantom, demonstrating that US-induced MBs inertial cavitation can effectively disrupt calcified plaques and reduce the inflation threshold of PTCA. The ex vivo histopathology results showed that the endothelium of pig blood vessels remained intact after the treatment. In summary, the results show that US-induced MBs inertial cavitation can markedly reduce the inflation threshold in PTCA without damaging blood vessel endothelia, indicating the potential of the proposed treatment method.

Review of intravascular lithotripsy for treating coronary, peripheral artery, and valve calcifications

Management of intracoronary calcium (ICC) continues to be a challenge for interventional cardiologists. There have been significant advances in calcium treatment devices. However, there still exists a knowledge gap regarding which devices to choose for the treatment of ICC. The purpose of this manuscript is to review the principles of intravascular lithotripsy (IVL) and clinical data. The technique of IVL will then be compared to alternative calcium treatment devices. Clinical data will be reviewed concerning the treatment of coronary, peripheral artery and valvular calcifications. Controversies to be discussed include how to incorporate IVL into your practice, what is the best approach for treating calcium subtypes, how to approach under-expanded stents, what is the ideal technique for performing IVL, how safe is IVL, whether imaging adds value when performing IVL, and how IVL fits into a treatment program for peripheral arteries and calcified valves.

Coronary Artery Calcification: Current Concepts and Clinical Implications

Coronary artery calcification (CAC) accompanies the development of advanced atherosclerosis. Its role in atherosclerosis holds great interest because the presence and burden of coronary calcification provide direct evidence of the presence and extent of coronary artery disease; furthermore, CAC predicts future events independently of concomitant conventional cardiovascular risk factors and to a greater extent than any other noninvasive biomarker of this disease. Nevertheless, the relationship between CAC and the susceptibility of a plaque to provoke a thrombotic event remains incompletely understood. This review summarizes the current understanding and literature on CAC. It outlines the pathophysiology of CAC and reviews laboratory, histopathological, and genetic studies, as well as imaging findings, to characterize different types of calcification and to elucidate their implications. Some patterns of calcification such as microcalcification portend increased risk of rupture and cardiovascular events and may improve prognosis assessment noninvasively. However, contemporary computed tomography cannot assess early microcalcification. Limited spatial resolution and blooming artifacts may hinder estimation of degree of coronary artery stenosis. Technical advances such as photon counting detectors and combination with nuclear approaches (eg, NaF imaging) promise to improve the performance of cardiac computed tomography. These innovations may speed achieving the ultimate goal of providing noninvasively specific and clinically actionable information.

A large post-stenting intramural hematoma in the left anterior descending artery caused by a small intimal calcium spur; should we respect the calcium shape?

Coronary heavy calcification (HC) poses a sturdy challenge to percutaneous coronary intervention (PCI). Scores considering calcification length, thickness, or circumferential extent, are widely accepted to dictate upfront calcium modification to improve PCI outcomes. Although often marginalized, calcification shape (morphology) may require consideration during procedure planning in selected cases. This case demonstrates how a focal but spur-shaped calcification led to a massive proximal left anterior descending (LAD) dissecting intramural hematoma.

Coronary calcification in patients presenting with acute coronary syndromes: insights from the MATRIX trial

AIMS

The role of coronary calcification on clinical outcomes among different revascularization strategies in patients presenting with acute coronary syndromes (ACSs) has been rarely investigated. The aim of this investigation is to evaluate the role of coronary calcification, detected by coronary angiography, in the whole spectrum of patients presenting with acute ACS.

METHODS AND RESULTS

The present study was a post hoc analysis of the MATRIX programme. The primary endpoint was major adverse cardiovascular events (MACE), defined as the composite of all-cause mortality, myocardial infarction (MI), or stroke up to 365 days. Among the 8404 patients randomized in the MATRIX trial, data about coronary calcification were available in 7446 (88.6%) and therefore were included in this post hoc analysis. Overall, 875 patients (11.7%) presented with severe coronary calcification, while 6571 patients (88.3%) did not present severe coronary calcification on coronary angiography. Fewer patients with severe coronary calcification underwent percutaneous coronary intervention whereas coronary artery bypass grafting or medical therapy-only was more frequent compared with patients without severe calcification. At 1-year follow-up, MACE occurred in 237 (27.1%) patients with severe calcified coronary lesions and 985 (15%) patients without severe coronary calcified lesions [hazard ratio (HR) 1.91; 95% confidence interval (CI) 1.66-2.20, P < 0.001]. All-cause mortality was 8.6% in patients presenting with and 3.7% in those without severe coronary calcification (HR 2.38, 1.84-3.09, P < 0.001). Patients with severe coronary calcification incurred higher rate of MI (20.1% vs. 11.5%, HR 1.81; 95% CI 1.53-2.1, P < 0.001) and similar rate of stroke (0.8% vs. 0.6%, HR 1.35; 95% CI 0.61-3.02, P = 0.46).

CONCLUSION

Patients with ACS and severe coronary calcification, as compared to those without, are associated with worse clinical outcomes irrespective of the management strategy.

Rotational Atherectomy Versus Intravascular Lithotripsy for Calcified In-Stent Restenosis: A Single-Center Study With 1-Year Follow-Up

Although rotational atherectomy (RA) and intravascular lithotripsy (IVL) have been proved to be effective for calcified de novo coronary lesions, their use in patients with in-stent restenosis (ISR) is still controversial. No comparison of these techniques in patients with ISR has been published so far. We sought to evaluate safety and feasibility of RA and IVL in patients with calcified ISR. Furthermore, we aimed to compare in-hospital and 1-year clinical outcomes between both groups. This is a retrospective single-center study evaluating patients with calcified ISR treated with RA (between 2012 and 2021) and IVL (between 2019 and 2021). Inhospital and 1-year clinical outcomes were compared between IVL and RA patients. In total, 28 patients with ISR who underwent RA were compared with 24 ISR subjects after IVL. The procedural success rate was 100% in both the groups. Quantitative coronary analysis demonstrated a similar degree of stenosis prior (66.4 ± 11.4 vs 68.8 ± 19.7, p = nonsignificant [NS]), and after the procedure (21.5 ± 20.5 vs 22.8 ± 12.1, p = NS) with no difference in acute luminal gain (1.34 ± 0.60 vs 1.38 ± 0.59, p = NS). There was one in-hospital major adverse cardiovascular event in the RA group. At 1-year follow-up, no difference was observed with respect to major adverse cardiovascular event rate (14.3% vs 16.7%, p = NS) and target vessel revascularization (7.1% vs 12.5%, p = NS). In conclusion, RA and IVL are safe and feasible techniques for calcified ISR yielding comparable results at 1-year follow-up. Further clinical studies are warranted to confirm our findings and shed more light on patient and lesion characteristics associated with the best outcomes.

Early experience of intravascular lithotripsy in unprotected calcified left main coronary artery disease

BACKGROUND

Treatment of unprotected severely calcified left main coronary artery (LMCA) disease is a complex interventional procedure. Intravascular lithotripsy (IVL) and rotational atherectomy (RA) are safe and effective methods of treating coronary calcification in the non-LMCA setting. This retrospective analysis assessed the feasibility of IVL versus RA in unprotected LMCA disease.

METHODS

We analyzed IVL and RA procedures performed at a large tertiary hospital in the Northeast of England from January 1, 2019 to April 31, 2022. Major safety and efficacy endpoints were procedural and angiographic success, defined by stent delivery with <50 % residual stenosis and without clinical or angiographic complications, respectively. Another important clinical endpoint was the composite of major adverse cardiac events (MACE) at 1 year.

RESULTS

From 242 patients, 44 had LMCA IVL, 81 had LMCA RA and 117 had non-LMCA IVL. Patients with LMCA disease were older and more likely to have aortic stenosis. IVL was a second-line or bailout technique in 86.4 % LMCA and 92.2 % non-LMCA cases. Procedural and angiographic success rates were ≥ 84 % across all groups (p > 0.05). In 3 LMCA IVL and 3 LMCA RA cases arrhythmias and cardiac tamponade complicated the procedures respectively. At 1 year, MACE occurred in 10/44 (22.7 %) LMCA IVL, 16/81 (19.8 %) LMCA RA and 25/117 (21.4 %) cases (p > 0.05).

CONCLUSION

In our single center retrospective analysis, IVL is feasible in unprotected calcified LMCA as a second-line and third-line adjuvant calcium modification technique. Its use in unprotected calcified LMCA disease should be formalized with the undertaking of large randomized controlled trials.

Coronary Intra-orbital Atherectomy Complications and Procedural Failure: Insight From the Manufacturer and User Facility Device Experience (MAUDE) Database

BACKGROUND

The Diamondback 360® Coronary Orbital Atherectomy System (Cardiovascular Systems Inc., St. Paul, MN) is the first and only orbital atherectomy system approved by the US FDA for the treatment of severely calcified lesions. While the device has proven to be safe in clinical trials, real-world data are minimal.

METHODS

The Manufacturer and User Facility Device Experience (MAUDE) database was queried for reports on the Diamondback 360® Coronary from January 2019 to January 2022.

RESULTS

A total of 566 events were reported during the study period. After the exclusion of duplicate reports, the final cohort included 547 reports. The most common mode of failure was break or separation of a device part (40.4%, n = 221) mainly due to breaking in the tip of the ViperWire (66.1%), driveshaft (22.7%), or crown (12.2%). The most common vessel associated with events was the left anterior descending artery (31.4%), followed by the right coronary artery (26.9%), left circumflex (21.6%), and left main coronary artery (6.4%). The most common clinical adverse outcome was perforation (33.0%, n = 181) with 23.7% resulting in cardiac tamponade. Most perforation cases were treated by covered stent (44.2%), surgery (30.5%), stent (98%), and balloon angioplasty (9%). There were 89 (16.3%) events of death with 67% due to perforation (p < 0.001).

CONCLUSION

Our study provided a glimpse of real-world adverse outcomes and common modes of failure due to orbital atherectomy. The most common mode of failure was the break or separation of a device part and the most common complication was perforation according to the MAUDE database. It will help physicians to anticipate complications and escalate care appropriately.

Prediction of the debulking effect of rotational atherectomy using optical frequency domain imaging: a prospective study

This study determined the predictive accuracy of optical frequency domain imaging (OFDI) on debulking effects of rotational atherectomy (RA) and compared the predictive accuracy of OFDI catheter-based with Rota wire-based prediction methods. This prospective, single-center, observational study included 55 consecutive patients who underwent OFDI-guided RA. On pre-RA OFDI images, a circle, identical to the Rota burr was drawn at the center of the OFDI catheter (OFDI catheter-based prediction method) or wire (wire-based prediction method). The area overlapping the vessel wall was defined as the predicted ablation area (P-area). The actual ablated area (A-area) was measured by superimposing the OFDI images before and after RA. The overlapping P-area and A-area were defined as overlapped ablation area (O-area), and the predictive accuracy was evaluated by %Correct area (O-area/P-area) and %Error area (A-area  - O-area/A-area). The median %Correct and %Error areas were 47.8% and 41.6%, respectively. Irrelevant ablation (low %Correct-/high % Error areas) and over ablation (high %Correct-/high % Error areas) were related to deep vessel injury and intimal flap outside the P-area. The predictive accuracy was better in the OFDI catheter-based prediction method than the wire-based prediction method in the cross sections where the OFDI catheter and wire came in contact. However, it was better in the latter than the former where the OFDI catheter and wire were not in contact. OFDI-based simulation of the RA effect is feasible though accuracy may be affected by the OFDI catheter and wire position. OFDI-based simulation of RA effect might reduce peri-procedural complications during RA.

Contribution of the Optical Coherence Tomography in Calcified Lesions

Coronary artery calcification is a complex process found predominantly in the elderly population. Coronary angiography frequently lacks sensitivity to detect, evaluate and quantify these lesions. Yet calcified lesions are considered stable, it remains associated with a higher rate of peri procedural complications during percutaneous coronary intervention (PCI) including an increased risk of stent under expansion and struts mal apposition leading to poor clinical outcome. Intracoronary imaging (Intravascular Ultra Sound (IVUS) and Optical Coherence Tomography (OCT)) allows better calcified lesions identification, localization within the coronary artery wall (superficial or deep calcifications), quantification. This lesions characterization allows a better choice of dedicated plaque-preparation tools (modified balloons, rotational or orbital atherectomy, intravascular lithotripsy) that are crucial to achieve optimal PCI results. OCT could also assess the impact of these tools on the calcified plaque morphology (plaque fracture, burring effects…). An OCT-guided tailored PCI strategy for calcified lesions still requires validation by clinical studies which are currently underway.

Shock Wave Intravascular Lithotripsy: Shock the Rock

Complex coronary artery disease with severe coronary calcification can be challenging to treat, with a higher risk of procedural complications and major adverse cardiac events. Intravascular lithotripsy (IVL) is a pioneering technology for the treatment of critically calcified coronaries. IVL utilizing localized pulsatile sonic pressure waves at low pressure provides a novel approach for lesion preparation of severely calcified plaques. The deliverability and ease of use are also likely to increase access and use of IVL, and combination therapy with other devices shows promise.

Treatment of In-Stent Restenosis Using a Dedicated Super High-Pressure Balloon

BACKGROUND

Treatment of in-stent restenosis (ISR) is challenging and treatment failure rate remains high. Correction of stent under-expansion and neointimal compression using the twin-layer OPN™ highly non-compliant balloon (NCB) at high pressure (>30 atm) may lead to increased luminal gain and thus better clinical outcomes. We evaluated periprocedural safety and clinical long-term outcomes after ISR treatment using the OPN™ NCB in a real-world population.

METHODS

From an ongoing registry, consecutive ISR patients treated with the OPN™ NCB at a tertiary cardiology center in Switzerland were analyzed. We evaluated procedural efficacy, periprocedural complications, target lesion/vessel failure (TLF/TVF), and major adverse cardiovascular events (MACE).

RESULTS

Totally, 208 ISR lesions were treated in 188 patients (mean age 68 ± 13 years, 78 % males). Most lesions were moderately to heavily calcified (89 %), the majority (70.2 %) had complex lesion characteristics (AHA Type B2/C lesions) and 50.5 % were non-focal ISR lesions. After ISR treatment using high pressure pre- and post-dilatation (mean pressure 33 ± 6 atm) with the OPN™ NCB device, the rate of major complications was low (0.96 % coronary perforation, 4 % major dissections, 1.9 % no-reflow and 0.5 % acute vessel closure). At 1-year follow-up, MACE occurred in 19.7 %; 15.4 % patients had TVF; MI and stent thrombosis was found in 5.9 % and 2.1 % of all patients, respectively; and 5 patients died.

CONCLUSIONS

For ISR treatment, using the super non-compliant OPN™ balloon at very high pressures is safe. Moreover, its use might lead to a low rate of TLF/TVF during long-term follow-up, but this requires further evaluation in dedicated comparative trials.

Shockwaves delivery for aortic valve therapy-Realistic perspective for clinical translation?

Calcific aortic valve disease (CAVD) is the most frequent valvular heart disorder, and the one with the highest impact and burden in the elderly population. While the quality and standardization of the current aortic valve replacements has reached unprecedented levels with the commercialization of minimally-invasive implants and the design of procedures for valve repair, the need of supplementary therapies able to block or retard the course of the pathology before patients need the intervention is still awaited. In this contribution, we will discuss the emerging opportunity to set up devices to mechanically rupture the calcium deposits accumulating in the aortic valve and restore, at least in part, the pliability and the mechanical function of the calcified leaflets. Starting from the evidences gained by mechanical decalcification of coronary arteries in interventional cardiology procedures, a practice already in the clinical setting, we will discuss the advantages and the potential drawbacks of valve lithotripsy devices and their potential applicability in the clinical scenario.

Long-term outcomes following intravascular lithotripsy (IVL) for calcified coronary lesions: A Real-World Multicenter European Study

OBJECTIVES

To explore the long-term clinical outcomes following intravascular lithotripsy (IVL) in calcified coronary lesions from a real-world population.

BACKGROUND

IVL is a relatively new but promising modality for treating coronary calcified lesions, but there is a dearth of long-term outcome data from real-world patients.

METHODS

This was a multicenter, observational study in which we enrolled all patients treated with IVL from November 2018 to February 2021 from eight centers in Europe and the United Kingdom. Procedural success, complications, and clinical outcomes (cardiac death, target vessel myocardial infarction [TVMI], target lesion revascularization [TLR], and MACE [major adverse cardiac events, the composite of cardiac death, TVMI, and TLR]) were assessed.

RESULTS

In total, 273 patients with a mean age of 72 ± 9.1 years were treated with IVL. Major comorbidities included diabetes mellitus (n = 110, 40%) and chronic kidney disease (n = 45, 16%). Acute coronary syndrome accounted for 48% (n = 132) of patients, while 52% (n = 141) had stable angina. De novo lesions and in-stent restenosis accounted for 79% and 21% of cases, respectively. Intravascular imaging was used in 33% (n = 90) of patients. An upfront IVL strategy was adopted in 34% (n = 92), while the rest were bailout procedures. Adjuvant rotational atherectomy ("RotaTripsy") was required in 11% (n = 31) of cases. The procedural success was 99%. During a median follow-up of 687 days (interquartile range: 549-787), cardiac death occurred in 5% (n = 14), TVMI in 3% (n = 8), TLR in 6% (n = 16), and MACE rate was 11% (n = 30).

CONCLUSION

This is the largest multicenter registry with a long-term follow-up showing the remarkably high procedural success of IVL use in calcified coronary lesions with low rates of hard endpoints and MACE.

Initial experience with orbital atherectomy in a tertiary centre in the Netherlands

Background

In January 2021, the Diamondback 360 orbital atherectomy (OA) system received CE mark approval and became available in Europe. The first procedure in Europe was performed at the Thoraxcenter, Erasmus Medical Center, Rotterdam, the Netherlands.

Aims

To report the procedural safety and efficacy of the initial experience with OA in a tertiary care institution in the Netherlands.

Methods

Patients with de novo severely calcified coronary artery disease who were treated with intended invasive imaging-guided OA were included in a prospective single-centre registry. Device success, defined as less than 50% stenosis after OA, and procedural success, defined as successful stent implantation with less than 50% residual stenosis, were evaluated. Calcium debulking effects were assessed by invasive imaging. Safety was assessed up to 30 days after the index procedure.

Results

Between February 2021 and June 2021, 29 patients with a total of 39 coronary arteries underwent OA. Target lesions were heavily calcified with a mean length of 32 mm and a calcium arc of 320 degrees. Invasive imaging was applied in all but one patient and 36 vessels. Superficial sanding was observed in almost all vessels (90%) and fracturing of deeper medial calcium in more than half of the vessels (63%), with a device success of 66% and procedural success of 94%. The mean stent symmetry index was 0.84, indicating good circular stent expansion. No primary safety events occurred during 30 days of follow-up.

Conclusion

Our initial experience with OA for heavily calcified coronary lesions demonstrated favourable debulking effects and plaque modification, with high procedural success and clinical safety.

Rota-Lithotripsy as a Novel Bail-Out Strategy for Highly Calcified Coronary Lesions in Acute Coronary Syndrome

Background: Heavily calcified lesions in acute coronary syndrome (ACS) still represent a challenging subset for percutaneous coronary intervention (PCI). Rota-lithotripsy—a marriage of rotational atherectomy and intravascular lithotripsy—has recently been introduced to clinical practice as a novel therapeutic option. Methods: This study is among the to present the 6-month clinical outcomes of rota-lithotripsy when performed in the ACS setting. The study cohort consisted of 15 consecutive ACS patients who underwent a rota-lithotripsy-PCI due to the presence of a highly calcified, undilatable lesion. Results: The procedural success ratio reached 100%. During the 6-month follow-up, in two of the patients, instances of MACE (major adverse cardiac events) occurred, including one fatal event. Additionally, during the observation period, one target lesion failure, due to subacute stent thrombosis, was identified. Conclusions: Rotational atherectomy with the subsequent use of shockwave intravascular lithotripsy appears to be a safe and effective therapeutic bail-out option for the management of highly calcified coronary artery lesions. Despite, these initial favorable outcomes, carrying out a large number of studies with long-term observations is still necessary in order to establish the potential benefits and shortcomings of rota-lithotripsy.

Coronary lithotripsy for the treatment of underexpanded stents: the international & multicentre CRUNCH registry

BACKGROUND

Stent underexpansion increases the risk of cardiac adverse events. At present, there are limited options to treat refractory stent underexpansion. In this context, the intravascular lithotripsy (IVL) system might be a safe and effective strategy.

AIMS

We aimed to evaluate the safety and efficacy of IVL in addressing resistant stent underexpansion due to heavy underlying calcification.

METHODS

This was an international multicentre registry including patients receiving IVL therapy to treat stent underexpansion from December 2017 to August 2020. Angiographic and intracoronary imaging data were collected. The efficacy endpoint was device success (technical success with a final percentage diameter stenosis <50%). The safety endpoint was in-hospital major adverse cardiac events (MACE).

RESULTS

Seventy patients were included, the mean age was 73±9.2 years and 76% were male. The median time from stent implantation to IVL therapy was 49 days (0-2,537). Adjuvant treatment with non-compliant balloon dilatations pre- and post-IVL was performed in 72.3% and 76.8% of patients, respectively, and additional stenting was performed in 22.4%. Device success was 92.3%. Minimum lumen diameter increased from 1.49±0.73 mm to 2.41±0.67 mm (p<0.001) and stent expansion increased by 124.93±138.19% (p=0.016). No IVL-related procedural complications or MACE were observed. The use of bailout IVL therapy directly after stenting and the presence of ostial underexpanded lesions negatively predicted lumen diameter gain.

CONCLUSIONS

Coronary lithotripsy is safe and effective in increasing lumen and stent dimensions in underexpanded stents secondary to heavily calcified lesions.

Intravascular lithotripsy during percutaneous coronary intervention: current concepts

INTRODUCTION

Coronary artery calcification (CAC) is commonly encountered by interventional cardiologists. Severe CAC may impair stent delivery or result in stent underexpansion, stent thrombosis and/or in-stent restenosis (ISR). Multiple tools have been developed to help overcome the challenges associated with CAC and improve outcomes for these patients. Intravascular shockwave lithotripsy (IVL) is a novel therapy that uses acoustic pressure waves for the modification of CAC.

AREAS COVERED

This review discusses the growing body of evidence to support the safety and efficacy of IVL in the setting of de novo severely calcified coronary arteries prior to stenting. We also discuss international real world experience with the coronary IVL system. This includes the use of IVL in the setting of acute coronary syndrome (ACS), ISR and in combination with other tools for calcium modification.

EXPERT OPINION

IVL is a safe and effective therapy that results in the fracture of coronary calcium and facilitates optimal stent delivery and expansion. Longer term follow up is essential to shed light on the durability and late outcomes of an IVL strategy. Randomised control trials are warranted to compare IVL to alternative methods of calcium modification and to explore further the use of IVL for ACS.

3-Year outcomes in patients with heavily calcified lesions undergoing percutaneous coronary intervention using cutting balloons

Background

Percutaneous coronary intervention (PCI) of heavily calcified lesions (HCLs) is associated with higher complication rates and worse clinical outcomes. Cutting balloon (CB) has been widely used for HCLs, but patients’ prognosis had not been fully clarified. The study aimed to compare 3-year clinical outcomes between patients with HCLs that are treated with CBs and those with non-HCLs.

Method

Patients who underwent PCI in Guizhou Provincial People’s Hospital from June 2015 to September 2018 were retrospectively included. HCL was defined as radiopaque and high-pressure undilatable lesions. CBs were routinely used in combination with non-compliant balloons for the HCLs. Major adverse cardiac event (MACE) and target vessel failure (TVF) were assessed at 3-year follow-up.

Result

Among 2432 patients included in the study, 210(8.6%) had HCLs with a procedural success rate of 91.0%. The patients with HCLs had a higher incidence of MACE (23.3% vs. 10.8%, P < 0.001) than those with non-HCLs. By propensity score matching, 172 patients with HCLs were 1:1 paired to those with non-HCLs, and their PCI vessels were exactly matched. The MACE and TVF were significantly higher in the patients with HCLs than those with non-HCLs (MACE: 21.5% vs. 13.4%, P = 0.036; TVF: 19.8% vs. 9.9%, P = 0.008). In the Cox regression analysis, HCL is independently associated with higher risks of MACE [HR: 1.72(1.01–2.94), P = 0.047], TVF [HR: 2.10(1.15–3.81), P = 0.015] and repeat revascularization [HR: 2.20(1.07–4.52), P = 0.032].

Conclusion

Patients with HCLs undergoing PCI using CBs in combination with non-compliant balloons had higher risks of complications, procedural failure, and worse clinical outcomes at 3 years than those with non-HCLs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02622-9.

Plaque modification in calcified chronic total occlusions: the PLACCTON study

INTRODUCTION AND OBJECTIVES

Severe calcification is present in> 50% of coronary chronic total occlusions (CTOs) undergoing percutaneous intervention. We aimed to describe the contemporary use and outcomes of plaque modification devices (PMDs) in this context.

METHODS

Patients were included in the prospective, consecutive Iberian CTO registry (32 centers in Spain and Portugal), from 2015 to 2020. Comparison was performed according to the use of PMDs.

RESULTS

Among 2235 patients, wire crossing was achieved in 1900 patients and PMDs were used in 134 patients (7%), requiring more than 1 PMD in 24 patients (1%). The selected PMDs were rotational atherectomy (35.1%), lithotripsy (5.2%), laser (11.2%), cutting/scoring balloons (27.6%), OPN balloons (2.9%), or a combination of PMDs (18%). PMDs were used in older patients, with greater cardiovascular burden, and higher Syntax and J-CTO scores. This greater complexity was associated with longer procedural time but similar total stent length (52 vs 57mm; P=.105). If the wire crossed, the procedural success rate was 87.2% but increased to 96.3% when PMDs were used (P=.001). Conversely, PMDs were not associated with a higher rate of procedural complications (3.7 vs 3.2%; P=.615). Despite the worse baseline profile, at 2 years of follow-up there were no differences in the survival rate (PMDs: 94.3% vs no-PMDs: 94.3%, respectively; P=.967).

CONCLUSIONS

Following successful wire crossing in CTOs, PMDs were used in 7% of the lesions with an increased success rate. Mid-term outcomes were comparable despite their worse baseline profile, suggesting that broader use of PMDs in this setting might have potential technical and prognostic benefits.

Best Practice in Intravascular Lithotripsy

Intravascular lithotripsy (IVL) is a novel approach to lesion preparation of severely calcified plaques in coronary and peripheral vessels. Lithotripsy is delivered by vaporising fluid to create an expanding bubble that generates sonic pressure waves that interact with arterial calcification. Available data indicate that IVL leads to increased vessel compliance before stent implantation with high efficacy and an excellent safety profile. Since it gained the CE mark in 2017, and with improved operator experience, the use of IVL has expanded into more complex clinical situations. This review focuses on the best practice for IVL use in the cath lab, based on 3 years of experience with the technology and the latest scientific data from the Disrupt CAD clinical trials.

One-year outcomes in patients who underwent coronary intravascular shockwave lithotripsy for highly-calcified coronary lesions

Intravascular lithotripsy (IVL) is associated with excellent angiographic and short-term results in patients with calcified lesions requiring percutaneous coronary intervention. We conducted a 1-year follow up of a retrospective cohort of 47 patients (61 lesions) who underwent IVL. The primary outcome was target vessel revascularization (TVR) at 1-year from index procedure. Four percent of patients required TVR within 1 year; 96% who underwent IVL remained free from repeat intervention on the same vessel. One patient suffered a myocardial infarction; the culprit vessel had not been previously treated with IVL. IVL is an effective and durable modality for treatment of highly calcified coronary lesions in high-risk patients.

Type E coronary artery dissection caused by intravascular lithotripsy balloon rupture; vessel anatomy and characteristics in a lithoplasty complication case as detailed by optical coherence tomography: a case report

BACKGROUND

Intravascular lithotripsy is a new method used to treat calcified coronary lesions (CCLs). Percutaneous coronary intervention of CCLs has conventionally been classified as a complex procedure. In the majority of calcified cases, atherectomy is required for sufficient plaque modification prior to stent implantation. Intravascular lithotripsy has been shown to be safe and effective in clinical trials, but as worldwide usage increases, cases of complications are beginning to emerge.

CASE SUMMARY

We describe a 71-year-old woman, who after an episode of non-ST-elevation acute coronary syndrome underwent coronary angiography. The culprit vessel was identified to be a severely stenosed left anterior descending artery which was also heavily calcified and tortuous. Intravascular lithotripsy (IVL) was employed for calcium modification prior to stent implantation, but the IVL balloon ruptured during shockwave lithotripsy, resulting in coronary artery dissection. Subsequent management steps and stent deployment resulted in favourable angiographic results. Our findings are further detailed on optical coherence tomography, demonstrating certain features which might predispose to IVL balloon rupture.

DISCUSSION

We discuss the mechanism of action during intravascular lithotripsy, and how the shockwaves from the lithotripter modify calcified lesions, whilst keeping soft tissue unharmed. Results from clinical trials and multiple real-world studies have shown that complication rates are low. This case report aims to illustrate how the rupture of an intravascular lithotripsy balloon can result in coronary artery dissection. Optical coherence tomography can help in identifying potential anatomical features which may precede such complications.

Comparative study of costs and resource utilisation of rotational atherectomy versus intravascular lithotripsy for percutaneous coronary intervention

BACKGROUND

Intravascular lithotripsy (IVL) is a novel alternative to rotational atherectomy (RA) for the modification of heavily calcified coronary stenoses prior to percutaneous coronary intervention (PCI). We compare the real-world resource utilisation and associated costs of PCI with adjunctive RA and IVL.

METHODS

We compared the resource utilisation, in-lab consumable costs and procedural data of 120 patients who underwent PCI with IVL from the Disrupt-CAD II study (NCT03328949) to 60 patients who underwent PCI with RA at the Golden Jubilee National Hospital, Glasgow. The RA patients were consecutive and selected on the basis of being deemed suitable for IVL by an independent interventional cardiologist experienced in the use of both techniques.

RESULTS

PCI with IVL was associated with significantly lower costs than PCI with RA (mean difference £398 [95% CI, £181-£615]; p<0.001). Considering between-group differences, the IVL group used 4.02 fewer balloons (p<0.001), 3.03 fewer guidewires (p<0.001), 0.52 fewer guide catheters (p=0.001), 0.22 fewer guide extensions (p=0.004) and 1.03 fewer drug eluting stents (DES) (p<0.001) per case than the RA group. The IVL group had shorter procedural duration (mean difference 13.3 min [95% CI, 3.6-23.0]; p=0.008) but longer fluoroscopy times (mean difference 4.4 min [95% CI, 1.7-7.1]; p=0.002).

CONCLUSIONS

In this indirect comparison, we found that the higher initial device costs of IVL may be offset by a lower overall resource utilisation. Further research is required to confirm this, and future randomised trials should include a formal health economic analysis.

Pourquoi et comment j'utilise le Shockwave ?

Les lésions calcifiées coronaires ont une incidence croissante dans la pratique quotidienne de l'angioplastie coronaire et sont un des facteurs essentiels des CHIP (High Risk Percutaneous Coronary Intervention). La préparation de la plaque calcifiée est essentielle afin de permettre de bonnes expansion et apposition du stent, deux critères indispensables pour un bon résultat à court et long terme de l'angioplastie coronaire. Depuis 2017, le cathéter C₂ Shockwave Medical® dispose d'un marquage CE pour la préparation des lésions coronaires calcifiées natives avant l'implantation de stent par le mécanisme de lithotripsie intravasculaire. Ce système se distingue par sa facilité d'utilisation et un très haut niveau de sécurité procédurale, se positionnant comme un challenger des techniques usuelles de préparation de la plaque calcifiée. L'objectif de cette revue est de se focaliser sur le mécanisme d'action de la lithotripsie intracoronaire, les conditions d'utilisation optimale du device et de synthétiser les données de littérature les plus récentes.

Hemodynamic alternations following stent deployment and post-dilation in a heavily calcified coronary artery: In silico and ex-vivo approaches

In this work, hemodynamic alterations in a patient-specific, heavily calcified coronary artery following stent deployment and post-dilations are quantified using in silico and ex-vivo approaches. Three-dimensional artery models were reconstructed from OCT images. Stent deployment and post-dilation with various inflation pressures were performed through both the finite element method (FEM) and ex vivo experiments. Results from FEM agreed very well with the ex-vivo measurements, interms of lumen areas, stent underexpansion, and strut malapposition. In addition, computational fluid dynamics (CFD) simulations were performed to delineate the hemodynamic alterations after stent deployment and post-dilations. A pressure time history at the inlet and a lumped parameter model (LPM) at the outlet were adopted to mimic the aortic pressure and the distal arterial tree, respectively. The pressure drop across the lesion, pertaining to the clinical measure of instantaneous wave-free flow ratio (iFR), was investigated. Results have shown that post-dilations are necessary for the lumen gain as well as the hemodynamic restoration towards hemostasis. Malapposed struts induced much higher shear rate, flow disturbances and lower time-averaged wall shear stress (TAWSS) around struts. Post-dilations mitigated the strut malapposition, and thus the shear rate. Moreover, stenting induced larger area of low TAWSS (<0.4 Pa) and lager volume of high shear rate (>2000 s^-1), indicating higher risks of in-stent restenosis (ISR) and stent thrombosis (ST), respectively. Oscillatory shear index (OSI) and relative residence time (RRT) indicated the wall regions more prone to ISR are located near the malapposed stent struts.

Planned versus bailout rotational atherectomy: A systematic review and meta-analysis

BACKGROUND/PURPOSE

Rotational atherectomy (RA) plays a central role in the treatment of heavily calcified coronary artery lesions. Our aim was to compare periprocedural characteristics and outcomes of planned (PA) vs. bailout (BA) rotational atherectomy.

METHODS

We conducted a systematic review and performed a meta-analysis on studies which compared PA vs. BA strategy.

RESULTS

Five studies fulfilled the inclusion criteria, pooling a total of 2120 patients. There was no difference in procedural success, PA vs. BA risk ratio (RR) 1.03 and 95% confidence interval (95% CI) 0.99-1.07. Compared to BA, PA was associated with a shorter procedural time [mean difference (MD) -25.88 min, 95% CI -35.55 to -16.22], less contrast volume (MD -43.71 ml, 95% CI -69.17 to -18.25), less coronary dissections (RR 0.50, 95% CI 0.26-0.99), fewer stents (MD -0.20, 95% CI -0.29 to -0.11), and a trend favouring less periprocedural myocardial infarctions (MI) (RR 0.77, 95% CI 0.54-1.11). There was no difference in major adverse cardiovascular events on follow-up (RR 1.04, 95% CI 0.62-1.74), death (RR 0.98, 95% CI 0.59-1.64), MI (RR 1.16, 95% CI 0.62-2.18), target vessel revascularization (RR 1.40, 95% CI 0.83 to 2.36), stroke (RR 1.50, 95% CI 0.46-4.86) or stent thrombosis (RR 0.82, 95% CI 0.06-10.74); all PA vs. BA comparisons.

CONCLUSIONS

Compared to bailout RA, planned RA resulted in significantly shorter procedural times, less contrast use, lesser dissection rates and fewer stents used. The bailout RA approach appears to enhance periprocedural risk, but there is no difference on mid-term outcomes.

Super high-pressure balloon versus scoring balloon to prepare severely calcified coronary lesions: the ISAR-CALC randomised trial

BACKGROUND

The comparative efficacy of balloon-based techniques to prepare severely calcified coronary lesions before stenting remains poorly studied.

AIMS

We sought to compare stent expansion following preparation of severely calcified coronary lesions with either a super high-pressure balloon or a scoring balloon.

METHODS

In this randomised, open-label trial, patients with severely calcified coronary lesions were enrolled at five centres in Germany and Switzerland. After unsuccessful lesion preparation with a standard non-compliant balloon (<30% reduction of baseline diameter stenosis), participants were randomised to predilation with either a super high-pressure balloon or a scoring balloon before drug-eluting stent (DES) implantation. The primary endpoint of the study was stent expansion index as assessed by optical coherence tomography (OCT). The key secondary endpoints included angiographic, strategy and procedural success.

RESULTS

OCT data after DES implantation were available for 70 out of 74 patients (94.6%) enrolled. Lesion preparation with a super high-pressure balloon versus a scoring balloon led to a comparable stent expansion index (0.72±0.12 vs 0.68±0.13; p=0.22). Compared with the scoring balloon, the super high-pressure balloon increased the minimum lumen diameter (2.83±0.34 mm vs 2.65±0.36 mm; p=0.03) and reduced the diameter stenosis (11.6±4.8% vs 14.4±5.6%; p=0.02) without difference in terms of angiographic success (100% vs 97.3%; p>0.99). Strategy success (91.9% vs 83.8%; p=0.48) and procedural success (100% vs 89.2%; p=0.12) were numerically more frequent with the super high-pressure balloon versus the scoring balloon.

CONCLUSIONS

In patients with severely calcified coronary artery lesions, preparation with a super high-pressure balloon versus a scoring balloon was associated with comparable stent expansion on intravascular imaging and a trend towards improved angiographic performance. Visual summary. A ComparIson of Strategies to PrepAre SeveRely CALCified Coronary Lesions: the ISAR-CALC randomised trial.

Wolverine cutting balloon in the treatment of stent underexpansion in heavy coronary calcification: bench test using a three-dimensional printer and computer simulation with the finite-element method

Heavy coronary calcification hinders successful stent implantation, and cutting balloons can be used for post-dilation after stent deployment. However, evidence regarding its use is limited to case reports. Therefore, this study aimed to investigate in-stent dilation in circumferential coronary calcifications using Wolverine cutting balloons, compared with conventional non-compliance (NC) balloons. Circumferential coronary calcification models were designed based on the patient's intravascular ultrasound images. Three-dimensional printed models were subjected to bench tests and software analysis was performed using the finite-element method (FEM). As a result, the bench test showed that higher balloon pressure was needed to dilate the models with stent implantation, either using Wolverine (17.1 ± 2.7 atm) or NC Emerge (18.9 ± 1.8 atm), while lower pressure was needed in models without stents using Wolverine [11.7 ± 2.9 atm, analysis of variance (ANOVA) p < 0.001]. Furthermore, models without stents were all successfully cracked by Wolverine at the first dilation, while models with stent implantation needed more dilations (ANOVA p = 0.0132). The FEM showed similar results that the first principal stress was the highest in Wolverine-dilated models without stents. In conclusion, implanted stents significantly increase the difficulty of balloon dilation and adequate pretreatment is critical for successful coronary stenting.

New Advances in the Treatment of Severe Coronary Artery Calcifications

Coronary artery calcifications are always challenging scenarios for interventional cardiologists. Calcium content in coronary tree directly correlates with male sex, age, Caucasian ethnicity, diabetes, and chronic kidney disease. Intracoronary imaging is useful and necessary to understand calcific lesion features and plan the best percutaneous coronary intervention strategy. Thus, accurate evaluation of patient and lesion characteristics is crucial. For this reason, definition of calcific arc, length, and thickness can suggest the best procedure before stenting and final optimization. In our modern era, different devices are available and all are surprisingly promising.

The "RotaTripsy Plus" Approach in a Heavily Calcified Coronary Stenosis

Percutaneous treatment of heavily calcified coronary stenoses is one the most demanding setting, due to the high risk of acute and long-term complications. Various dedicated devices are currently available and their combined use can be an option in these high-risk procedures. We hereby report a successful case of several combined debulking technologies for the treatment of a long, highly calcified coronary lesion.

"RotaTripsy: Combination of rotational atherectomy and intravascular lithotripsy in heavily calcified coronary lesions: A case series"

Heavily calcified coronary lesions increase the complexity of percutaneous coronary interventions (PCI) and represent a challenge for interventional cardiologists. They are an important cause of stent underexpansion and poor clinical outcome. Nowadays, there are different dedicated devices which enhance the chances of success. Rotational atherectomy is the first-line modality which permits to cross balloons or stents through severe calcified lesions. However, when circumferential deep calcium plaques exist may not be enough to achieve adequate expansion of these devices. In these cases, the complementary use of intracoronary lithotripsy ("RotaTripsy") can be an effective approach that further modifies the calcified plaque and enables optimal stent implantation. We present the first case series undergoing PCI using "RotaTripsy" technique.

Radiation risk for patients undergoing cardiac computed tomography examinations

The various technological advancements in computed tomography (CT) have resulted in remarkable growth in the use of CT imaging in clinical practice, not the least of which has been its establishment as the most valuable imaging examination for the assessment of cardiovascular system disorders. The objective of this study was to assess the effective radiation dose and radiation risk for patients during cardiac CT procedures, based on studies from four different hospitals equipped with 128 slice CT equipment. A total of eighty-three patients were investigated in this study with different clinical indications. Effective doses were also calculated using software based on Monte Carlo simulation. The mean patient age (years), weight (kg), and body mass index (BMI (kg/m²)) were 49 ± 11, 82 ± 12, and 31 ± 6, respectively. The results of the study revealed that the tube voltage (kVp) and tube current-exposure time product (mAs) ranged between 100 to 140 and 50 to 840 respectively. The overall average patient dose values for the volume CT dose index [(CTDI_vol), in mGy)] and dose length product (DLP) (in mGy·cm) were 34.8 ± 15 (3.7-117.0) and 383.8 ± 354 (46.0-3277.0) respectively. The average effective dose (mSv) was 15.2 ± 8 (1.2-61.8). The radiation dose values showed wide variation between different hospitals and even within the same hospital. The results indicate the need to optimize radiation dose and to establish diagnostic reference levels (DRLs) for patients undergoing coronary computed tomography angiography (CCTA), also to harmonize the imaging protocols to ensure reduced radiation risk.

Current Treatment Modalities for Calcified Coronary Artery Disease: A Review Article Comparing Novel Intravascular Lithotripsy and Traditional Rotational Atherectomy

The coronary artery calcium score is considered the most useful marker for predicting coronary events. The high score reflects heavy calcification in the vessel, which is more challenging to treat with the percutaneous intervention (PCI). To prepare this type of heavily calcified lesion intravascular lithotripsy (IVL) technology can be used prior to PCI, which is based on the concept of converting electrical energy into mechanical energy. It harmlessly and selectively disrupts both the shallow and deep deposits of calcium. The balloon-based catheters of this system emit sonic waves that transfer to the adjacent tissue resulting in improvement in vessel compliance with the slightest soft tissue loss. Therefore, making the treatment of calcified lesions more feasible, effective, and also simplify complex lesions. The lesions considered for lithotripsy-enhanced balloon dilation include calcified coronary lesions and peripheral vasculature lesions. This article reviews the use of IVL in calcified coronary artery disease, its advantages, and disadvantages while comparing it with other techniques like high-pressure balloons and rotational atherectomy devices. A thorough search of databases like PubMed and Google Scholar was performed, which uncovered 35 peer review articles. Keywords utilized in the data search were calcified coronary artery disease, coronary lithotripsy, calcification, and calcified atherosclerotic plaque. According to rotational atherectomy and intravascular lithotripsy trials, the latter was safer, mainly by decreasing atheromatous embolization risk. Deciphering these studies, it seems like IVL is better at parameters like procedural and clinical success rate, acute lumen gain, and less residual stenosis except in-hospital major adverse cardiovascular events (MACE), which was better in rotational atherectomy (RA). However, when lesion crossings are present, the atherectomy technique is still considered as first-line therapy. In clinical practice, despite these encouraging data for treating calcified lesions, IVL is grossly underutilized because of substantial costs and perceived significant procedural risk effects on the cardiac rhythm like causing 'shock topics' and asynchronous cardiac pacing. More longer-term clinical data and extensive researches are required to validate its safety and efficiency.

Use of Lithotripsy in a Calcified Saphenous Vein Graft

Percutaneous coronary interventions in saphenous vein grafts can pose a variety of challenges, such as severely calcified lesions. If these lesions are nondilatable, lithotripsy can arguably be a proper tool for lesion preparation. We present a case in which a nondilatable, calcified saphenous vein graft was successfully treated using Shockwave lithotripsy. (Level of Difficulty: Intermediate.)

Using the coronary lithotripsy system for coronary artery disease

Severe coronary artery calcification increases percutaneous treatment complexity and the risk of intraprocedural complications, affecting acute and long-term outcomes. Current use of specialty balloons and atherectomy technologies is limited due to the higher risk of complications, degree of technical difficulty and operator experience. Intravascular lithotripsy (IVL) is a novel technology for severe calcified coronary artery disease that facilitates vessel preparation, enhancing vessel compliance. IVL system emits sonic waves that penetrate through vascular layers and disrupt both superficial and deep calcium, leaving the soft tissue unharmed. The purpose of the present review is to provide a summary of the evidence currently available on this therapy, including a practical description of the components and function of the shockwave coronary IVL system.

Left Main Coronary Interventions: A Practical Guide

Coronary artery bypass surgery has been the accepted treatment for left main coronary artery disease for over 50 years. Balloon angioplasty was later used then abandoned because of deaths likely due to restenosis or thrombotic occlusion. However, rapid innovations in drug-eluting stent designs leading to more biocompatible thin strut platforms with optimal drug elution profiles and further advances in modern pharmacotherapy involving potent P2Y₁₂ inhibitors combined with utilization of intracoronary imaging and physiologic assessment for procedural planning and optimization have transformed percutaneous interventions into successful alternatives to coronary artery bypass graft surgery (CABG) in selected LM anatomic territories. Herein, we provide an evidence-based practical guide on how to approach and perform LM percutaneous interventions (PCI).