Principles of Intravascular Lithotripsy for Calcific Plaque Modification

Impact of coronary calcium morphology on intravascular lithotripsy

BACKGROUND

Coronary calcification negatively impacts optimal stenting. Intravascular lithotripsy (IVL) is a new calcium modification technique.

AIMS

We aimed to assess the impact of different calcium morphologies on IVL efficacy.

METHODS

This was a prospective, multicentre study (13 tertiary referral centres). Optical coherence tomography (OCT) was performed before and after IVL, and after stenting. OCT-defined calcium morphologies were concentric (mean calcium arc >180°) and eccentric (mean calcium arc ≤180°). The primary outcomes were angiographic success (residual stenosis <20%) and the presence of fracture by OCT in concentric versus eccentric lesions.

RESULTS

Ninety patients were included with a total of 95 lesions: 47 concentric and 48 eccentric. The median number of pulses was 60 (p=1.00). Following IVL, the presence of fracture was not statistically different between groups (79.0% vs 66.0% for concentric vs eccentric; p=0.165). The number of fractures/lesion (4.2±4.4 vs 2.3±2.8; p=0.018) and ≥3 fractures/lesion (57.1% vs 34.0%; p=0.029) were more common in concentric lesions. Angiographic success was numerically but not statistically higher in the concentric group (87.0% vs 76.6%; p=0.196). By OCT, no differences were noted in final minimum lumen area (5.9±2.2 mm2 vs 6.2±2.1 mm2; p=0.570), minimum stent area (5.9±2.2 mm² vs 6.25±2.4 mm2; p=0.483), minimum stent expansion (80.9±16.7% vs 78.2±19.8%), or stent expansion at the maximum calcium site (100.6±24.2% vs 95.8±27.3%) (p>0.05 for all comparisons of concentric vs eccentric, respectively). Calcified nodules were found in 29.5% of lesions; these were predominantly non-eruptive (57%). At the nodule site, dissection was more common than fracture with stent expansion of 103.6±27.2%.

CONCLUSIONS

In this prospective, multicentre study, the effectiveness of IVL followed by stenting was not significantly affected by coronary calcium morphology.

Extension of interval between adjacent pulse delivery cycles to deal with myocardial ischemia by intravascular lithotripsy: case report

BACKGROUND

Intravascular lithotripsy (IVL) represents a novel approach in the management of coronary calcification. This technique employs acoustic pressure waves, generated by a shockwave balloon, to effectively fracture both superficial and deep calcification in situ. The efficacy and safety of IVL have been convincingly demonstrated through the Disrupt CAD I-IV studies. While IVL is associated with the occurrence of atrial and ventricular arrhythmias, there is no evidence to indicate it causes myocardial ischemia.

CASE DESCRIPTION

A 71-year-old man was admitted presenting with chest pain. His previous coronary angiography revealed stenosis and calcification in the left anterior descending branch. An attempt to predilate the lesion using two Lacrosse non-slip element balloons was unsuccessful. Ventricular premature beats and transient ST-segment depression were captured during the utilization of IVL. The operator gradually extended the pulse emission interval across two consecutive cycles to mitigate myocardial ischemia. Notably, when the interval reached 30s, the patient had no chest pain or ST-segment changes. Subsequent images of intravascular ultrasound confirmed calcification ruptures. Therapeutic intervention included the placement of a stent and the application of a drug-coated balloon in the left anterior descending branch. A telephonic follow-up six months later indicated the patient had no discomfort.

CONCLUSIONS

This case underscores the effectiveness of gradually extending the pulse emission interval as a strategic complement to the clinical application of IVL. In certain clinical scenarios, it may become imperative to suspend the pulse delivery to improve myocardial blood supply.

Coronary Intravascular Lithotripsy

Coronary artery calcification is strongly associated with adverse cardiac events and can impede the success of percutaneous coronary intervention (PCI) due to challenges with delivery of equipment and expansion of stents. Current treatment modalities for mitigation of coronary calcification have limitations and inherent risk of complications. Coronary intravascular lithotripsy (IVL) is a novel technique to modify coronary artery calcification via acoustic pressure waves. IVL utilizes an easy-to-use device, which does not require a steep learning curve. Prospective studies have shown this technique to be safe and effective and can be used to adequately modify calcified coronary stenoses in preparation for PCI and stent deployment and optimization. IVL has unique features that can be used alone or as an adjunctive therapy to other available calcium modification tools. As compared to the currently established modalities of calcium modification, IVL has the potential to facilitate successful PCI with fewer serious procedural complications. In this review article, we discuss the importance of coronary artery calcification, the role of IVL, its mechanism, the current clinical data behind its use and future directions. Overall, coronary IVL is a promising technology for the treatment of severely calcified coronary stenoses, with a need for, long-term clinical outcome data of IVL-facilitated PCI.

Coronary Intravascular Lithotripsy Effectiveness and Safety in a Real-World Cohort

Background: Coronary artery calcification is a predictor of adverse outcomes after percutaneous coronary intervention (PCI). Intravascular lithotripsy (IVL) is a promising tool for the treatment of calcified lesions. The aim of this study was to assess the effectiveness and safety of IVL. Methods: A single-center observational study of PCI procedure, with assessment of the outcomes of patients undergoing PCI using IVL, was performed. Angiographic procedural success was used as the primary effectiveness endpoint. The primary safety endpoint was defined as a composite of cardiac death, myocardial infarction and target vessel revascularization within 30 days. Results: A total of 111 patients were included. Indications for PCI spanned the spectrum of chronic (53.2%) and acute coronary syndromes (43%). Lesion preparation before IVL was performed with non-compliant (42%), cutting or OPN (14.4%) balloons and with atherectomy techniques in 11% of procedures. Intravascular imaging was used in 21.6% of procedures. The primary effectiveness endpoint was achieved in 100% and the primary safety endpoint in 3.6% of procedures. Peri-procedural complications were minimal and successfully resolved. Conclusions: IVL was an effective and safe technique for the treatment of calcified coronary lesions. These findings contribute to the growing body of evidence supporting the use of IVL in the management of these challenging scenarios.

Efficacy of intravascular lithotripsy (IVL) in coronary stenosis with severe calcification: A multicenter systematic review and meta-analysis

BACKGROUND

With heavily calcified coronary and peripheral artery lesions, lesion preparation is crucial before stent placement to avoid underexpansion, associated with stent thrombosis or restenosis and patency failure in the long-term. Intravascular lithotripsy (IVL) technology disrupts superficial and deep calcium by using localized pulsative sonic pressure waves, making it to a promising tool for patients with severe calcification in coronary bed.

AIMS

The aim of the study is to systematically review and summarize available data regarding the safety and efficacy of IVL for lesion preparation in severely calcified coronary arteries before stenting.

METHODS

This study was conducted according to the PRISMA guidelines. We systematically searched PubMed, SCOPUS, and Cochrane databases from their inception to February 23, 2023, for studies assessing the characteristics and outcomes of patients undergoing IVL before stent implantation. The diameter of the vessel lumen before and after IVL, as well as stent implantation, were analyzed. The occurrence of major adverse cardiovascular events (MACE) was assessed using a random-effects model.

RESULTS

This meta-analysis comprised 38 studies including 2977 patients with heavily calcified coronary lesions. The mean age was 72.2 ± 9.1 years, with an overall IVL clinical success of 93% (95% confidence interval [CI]: 91%-95%, I2 = 0%) and procedural success rate of 97% (95% CI: 95%-98%, I2 = 73.7%), while the in-hospital and 30-days incidence of MACE, myocardial infarction (MI), and death were 8% (95% CI: 6%-11%, I2 = 84.5%), 5% (95% CI: 2%-8%, I2 = 85.6%), and 2% (95% CI: 1%-3%, I2 = 69.3%), respectively. There was a significant increase in the vessel diameter (standardized mean difference [SMD]: 2.47, 95% CI: 1.77-3.17, I2 = 96%) and a decrease in diameter stenosis (SMD: -3.44, 95% CI: -4.36 to -2.52, I2 = 97.5%) immediately after IVL application, while it was observed further reduction in diameter stenosis (SMD: -6.57, 95% CI: -7.43 to -5.72, I2 = 95.8%) and increase in the vessel diameter (SMD: 4.37, 95% CI: 3.63-5.12, I2 = 96.7%) and the calculated lumen area (SMD: 3.23, 95% CI: 2.10-4.37, I2 = 98%), after stent implantation. The mean acute luminal gain following IVL and stent implantation was estimated to be 1.27 ± 0.6 and 1.94 ± 1.1 mm, respectively. Periprocedural complications were rare, with just a few cases of perforations, dissection, or no-reflow phenomena recorded.

CONCLUSIONS

IVL seems to be a safe and effective strategy for lesion preparation in severely calcified lesions before stent implantation in coronary arteries. Future prospective studies are now warranted to compare IVL to other lesion preparation strategies.

Coronary intravascular lithotripsy for severe coronary artery calcification: The disrupt CAD I-IV trials

Coronary artery calcification (CAC) severity is associated with increased vessel inflammation, atherosclerosis, stent failure, and risk of percutaneous coronary intervention-related complications. Current modalities for CAC modification include atherectomy techniques (rotational, orbital, and laser) and balloon modification (cutting and scoring). However, these methods are limited by their risk of slow flow/no reflow, coronary dissection, perforation, and myocardial infarction. Intravascular lithotripsy (IVL) emits high-energy sonic waves that induce calcium fractures within a target lesion to improve vessel compliance for stent placement. Low rates of major cardiac adverse events (MACE) and high rates of procedural and angiographic success were observed with IVL in the Disrupt CAD I-IV trials. Optical coherence tomography sub-studies identified calcium fracture as the likely etiology of improved vessel compliance and increased luminal diameter post-IVL. Rates of MACE, procedural, and angiographic success were consistent across the Disrupt CAD trials, suggesting IVL is less operator-dependent compared to other calcium-modifying techniques. Coronary IVL offers interventional cardiologists a safe and effective method of severe CAC modification, while providing reproducible outcomes.

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.

Contemporary outcomes of chronic total occlusion percutaneous coronary intervention in Europe: the ERCTO registry

BACKGROUND

Percutaneous coronary interventions (PCI) of chronic total occlusions (CTO) have reached high procedural success rates thanks to dedicated equipment, evolving techniques, and worldwide adoption of state-of-the-art crossing algorithms.

AIMS

We report the contemporary results of CTO PCIs performed by a large European community of experienced interventionalists. Furthermore, we investigated the impact of different risk factors for procedural major adverse cardiac and cerebrovascular events (MACCE) and trends of employment of specific devices like dual lumen microcatheters, guiding catheter extensions, intravascular ultrasound and calcium-modifying tools.

METHODS

We evaluated data from 8,673 CTO PCIs included in the European Registry of Chronic Total Occlusion (ERCTO) between January 2021 and October 2022.

RESULTS

The overall technical success rate was 89.1% and was higher in antegrade as compared with retrograde cases (92.8% vs 79.3%; p<0.001). Compared with antegrade procedures, retrograde procedures had a higher complexity of attempted lesions (Japanese CTO [J-CTO] score: 3.0±1.0 vs 1.9±1.2; p<0.001), a higher procedural and in-hospital MACCE rate (3.1% vs 1.2%; p<0.018) and a higher perforation rate with and without tamponade (1.5% vs 0.4% and 8.3% vs 2.1%, respectively; p<0.001). As compared with mid-volume operators, high-volume operators had a higher technical success rate in antegrade and retrograde procedures (93.4% vs 91.2% and 81.5% vs 69.0%, respectively; p<0.001), and had a lower MACCE rate (1.47% vs 2.41%; p<0.001) despite a higher mean complexity of the attempted lesions (J-CTO score: 2.42±1.28 vs 2.15±1.27; p<0.001).

CONCLUSIONS

The adoption of different recanalisation techniques, operator experience and the use of specific devices have contributed to a high procedural success rate despite the high complexity of the lesions documented in the ERCTO.

Intravascular lithotripsy: A novel option for severe calcification of coronary artery

BACKGROUND

Severe coronary artery calcification is associated with low success rate of interventional operation, perioperative adverse cardiac events, and poor prognosis, which is a major problem faced by operators. The existing therapy methods all have inherent limitations, such as unsatisfactory balloon crossability, inadequate balloon dilation, and so on. The emergence of intravascular lithotripsy (IVL) has brought the dawn of the treatment of calcified lesions by using unfocused acoustic pressure waves to fracture calcification in situ. And IVL is the only technology capable of targeting deep calcification.

HYPOTHESIS

IVL may have great clinical application values and potential prospects.

METHOD

Based on the existing clinical evidence of IVL and traditional treatment ways, this review discusses the safety and efficacy of IVL. Combined with clinical practice, the precautions and coping strategies of IVL are analyzed. And the review improves the management algorithm of coronary calcification.

RESULTS

IVL has extremely high safety and effectiveness for severe coronary calcification compared with other ways, and structural improvements of IVL will further expand its value.

CONCLUSIONS

The emergence of IVL could set off a revolution in the treatment of coronary artery calcification.

Sex-specific analysis of intravascular lithotripsy for peripheral artery disease from the Disrupt PAD III observational study

OBJECTIVE

Endovascular therapy of lower extremity peripheral artery disease (PAD) is associated with higher complication rates and worse outcomes in women vs men. Although intravascular lithotripsy (IVL) has shown similarly favorable outcomes in men and women in calcified coronary arteries, there is no published safety and effectiveness data of peripheral IVL differentiated by sex. This study aims to evaluate sex-specific acute procedural safety and effectiveness following IVL treatment of calcified PAD.

METHODS

We performed a secondary analysis of the multicenter Disrupt PAD III Observational Study, which assessed short-term procedural outcomes of patients undergoing treatment of symptomatic calcified lower extremity PAD with the Shockwave peripheral IVL system. Adjudicated acute safety and efficacy outcomes were compared by sex using univariate analysis performed with the χ2 test or Fisher exact test, as appropriate.

RESULTS

A total of 1262 patients (29.9% women) were included, with >85% having moderate to severe lesion calcification. Women were older (74 vs 71 years; P < .001), had lower ankle-brachial index (0.7 vs 0.8; P = .003), smaller reference vessel size (5.3 vs 5.6 mm; P = .009), and more severe stenosis at baseline vs men (82.3% vs 79.8%; P = .012). Rates of diabetes, renal insufficiency, chronic limb-threatening ischemia, lesion length, and atherectomy use were similar in both groups. Residual stenosis after IVL alone was significantly reduced in both groups. Final residual stenosis was 21.9% in women and 24.7% in men (P = .001). Serious angiographic complications were infrequent and similar in both groups (1.4% vs 0.6%; P = .21), with no abrupt vessel closure, distal embolization, or thrombotic events during any procedure.

CONCLUSIONS

The use of IVL to treat calcified PAD in this observational registry demonstrated favorable acute safety and effectiveness in both women and men.

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.

Intravascular Lithotripsy in Peripheral Artery Disease

Peripheral artery disease affects millions of people worldwide, and it is associated with significantly higher morbidity and mortality. In addition, it represents a significant challenge for the interventional operators to appropriately and successfully revascularize heavily calcified stenoses. There are several established atherectomy devices with the risk of procedural complications including dissection and perforation, among others. Intravascular lithotripsy (IVL) is a novel tool with relatively less procedural risk compared to the existing modalities. It is a device that emits high-energy ultrasound waves mounted on a balloon catheter that causes fractures on the calcium plaques allowing balloon expansion and luminal gain. Five trials have been published showing the safety and effectiveness of IVL, including one trial evaluating the device in common femoral artery and infrapopliteal arteries. The available data from the limited number of trials are very encouraging and demonstrates minimal risk. Additional studies on a larger scale are needed further to understand the its long-term effects and possible risks.

Circumferential degree of tibial artery calcification is associated with infrapopliteal endovascular revascularization outcomes in patients with chronic limb-threatening ischemia

BACKGROUND

Tibial artery calcification (TAC) is correlated with an increased risk of amputation and mortality in patients with chronic limb-threatening ischemia (CLTI). The association between calcification characteristics and adverse limb events of CLTI. However, it has not been assessed. This study aims to assess the relationship between the characteristics of TAC based on computed tomography angiography (CTA) scans and postoperative outcomes in patients with CLTI undergoing infrapopliteal endovascular therapy.

METHODS

This was a retrospective study of patients who underwent infrapopliteal endovascular revascularization for CLTI and had a preoperative CTA scan. Based on CTA, TAC was divided into the following categories: annularity, thickness, continuity and severity. Cox regression models using generalized estimating equations were performed to assess the relationship between calcification characteristics and postoperative outcomes. The outcomes evaluated were the occurrence of all cause mortality (ACM) and unplanned amputation.

RESULTS

Among the 148 patients undergoing endovascular, there were 50 (33.8%) patients died and 26 (17.6%) patients underwent unplanned amputation. Annular calcification was more common in the ACM group than in the non-ACM group. No significant differences were found between the two groups with regard to the probability of calcification in the thickness and the continuity (P>0.05). Patients in the unplanned amputation group had significantly annular, thin and continuity calcifications (P<0.05) than those in the non-unplanned amputation group. The presence of annular calcification was an independent predictor of ACM (hazard ratio (HR), 3.186; 95% confidence interval (CI), 1.781-5.702; P<0.001) and unplanned amputation (HR, 3.739; 95% CI, 1.707-8.191; P<0.05).

CONCLUSIONS

Among patients with CLTI, the occurrence of annular calcification in the tibial artery are related to a greater chance of ACM and unplanned amputation in the postoperative period. The circumferential degree of TAC of the operated limb can be considered as a marker of clinical prognosis in this group of patients.

Evaluation of the thickness of coronary calcium by 60-MHz intravascular ultrasound: head-to-head comparison with optical frequency domain imaging

The region behind the coronary calcium could not be visualized by intravascular ultrasound (IVUS) because of acoustic shadow. However, some pathological studies have shown that IVUS delineated the vessel border behind thin coronary calcium sheets. This study aimed to reveal whether recent IVUS can visualize the region behind thin coronary calcium sheets. Using 534 cross-sectional optical frequency domain images (OFDI), including severe calcified coronary lesions, calcium sheet thickness was measured by every 1°. Accordingly, the visibility of the vessel border behind the coronary calcium sheet was evaluated using 60-MHz IVUS images, which were longitudinally linked with OFDI ones. After carefully coordinating with the axial position, the association between the IVUS-derived permeability of the coronary calcium sheet and calcium thickness was evaluated. The maximum and mean calcium thickness by OFDI was 0.88 ± 0.39 and 0.62 ± 0.30 mm, respectively. By 60-MHz IVUS, 12.1% of the coronary calcium sheets had permeable segments. Comparing between OFDI and IVUS images, 48.6% of the coronary calcium sheets with maximum thickness ≤ 0.3 mm were sometimes permeable by 60-MHz IVUS, whereas most > 0.5 mm thick calcium sheets were impermeable. In the receiver operating characteristic curve analysis, the best cutoff values for the maximum and mean thickness of permeable calcium were 0.48 and 0.31 mm, respectively. Thus, 60-MHz IVUS can occasionally visualize the region behind a thin coronary calcium sheet. When using 60-MHz IVUS, this finding may be a predictive marker of calcium sheet with a thickness of < 0.5 mm.

Management strategies for heavily calcified coronary stenoses: an EAPCI clinical consensus statement in collaboration with the EURO4C-PCR group

Since the publication of the 2015 EAPCI consensus on rotational atherectomy, the number of percutaneous coronary interventions (PCI) performed in patients with severely calcified coronary artery disease has grown substantially. This has been prompted on one side by the clinical demand for the continuous increase in life expectancy, the sustained expansion of the primary PCI networks worldwide, and the routine performance of revascularization procedures in elderly patients; on the other side, the availability of new and dedicated technologies such as orbital atherectomy and intravascular lithotripsy, as well as the optimization of the rotational atherectomy system, has increased operators' confidence in attempting more challenging PCI. This current EAPCI clinical consensus statement prepared in collaboration with the EURO4C-PCR group describes the comprehensive management of patients with heavily calcified coronary stenoses, starting with how to use non-invasive and invasive imaging to assess calcium burden and inform procedural planning. Objective and practical guidance is provided on the selection of the optimal interventional tool and technique based on the specific calcium morphology and anatomic location. Finally, the specific clinical implications of treating these patients are considered, including the prevention and management of complications and the importance of adequate training and education.

Endovascular Interventions for Peripheral Artery Disease: A Contemporary Review

PURPOSE OF REVIEW

Peripheral artery disease (PAD) is an increasingly prevalent but frequently underdiagnosed condition that can be associated with high rates of morbidity and mortality. While an initial noninvasive approach is the cornerstone of management, revascularization is often pursued for patients with treatment-refractory claudication or chronic limb-threatening ischemia (CLTI). In this review, we discuss the current state of endovascular interventions for PAD and explore the many new emerging technologies.

RECENT FINDINGS

The last decade has resulted in numerous advances in PAD interventions including the ongoing evolution of drug-coated devices, novel approaches to complex lesions, and contemporary evidence from large clinical trials for CLTI. Advances in endovascular management have allowed for increasingly complex lesions to be tackled percutaneously. Future directions for the field include the continued evolution in device technology, continued development of state-of-the-art techniques to revascularization of complex lesions, and increased collaboration between a largely multidisciplinary field.

Modified leopard-crawl technique using intravascular lithotripsy balloon in calcified coronary lesions

Intravascular lithotripsy (IVL) has emerged as a novel therapy for the treatment of coronary calcification. Numerous studies have reported the safety and efficacy of IVL in calcified coronary lesions, while IVL balloon-uncrossable calcified coronary lesions are sometimes encountered in clinical practice. This case report represents a novel technique called "modified leopard-crawl" to advance the IVL balloon antegradely by creating significant calcium cracking forward when the enhanced stent visualization system reveals that the distal emitter seems adjacent to calcification. This technique might be a valuable alternative when conventional procedures fail and has the potential to enhance the clinical applicability of IVL in daily practice.

A Systematic Review and Meta-Analysis Including 354 Patients from 13 Studies of Intravascular Lithotripsy for the Treatment of Underexpanded Coronary Stents

Calcified coronary plaque (CCP) represents a challenging scenario for interventional cardiologists. Stent underexpansion (SU), often associated with CCP, can predispose to stent thrombosis and in-stent restenosis. To date, SU with heavily CCP can be addressed using very high-/high-pressure noncompliant balloons, off-label rotational atherectomy/orbital atherectomy, excimer laser atherectomy, and intravascular lithotripsy (IVL). In this meta-analysis, we investigated the success rate of IVL for the treatment of SU because of CCP. Studies and case-based experiences reporting on the use of IVL strategy for treatment of SU were included. The primary end point was IVL strategy success, defined as the adequate expansion of the underexpanded stent. A metanalysis was performed for the main focuses to calculate the proportions of procedural success rates with corresponding 95% confidence intervals (CIs). Random-effects models weighted by inverse variance were used because of clinical heterogeneity. This meta-analysis included 13 studies with 354 patients. The mean age was 71.3 years (95% CI 64.9 to 73.1), and 77% (95% CI 71.2% to 82.4%) were male. The mean follow-up time was 2.6 months (95% CI 1 to 15.3). Strategy success was seen in 88.7% (95% CI 82.3 to 95.1) of patients. The mean minimal stent area was reported in 6 studies, the pre-IVL value was 3.4 mm2 (95% CI 3 to 3.8), and the post-IVL value was 6.9 mm2 (95% CI 6.5 to 7.4). The mean diameter stenosis (percentage) was reported in 7 studies, the pre-IVL value was 69.4% (95% CI 60.7 to 78.2), and the post-IVL value was 14.6% (95% CI 11.1 to 18). The rate of intraprocedural complications was 1.6% (95% CI 0.3 to 2.9). In conclusion, the "stent-through" IVL plaque modification technique is a safe tool to treat SU caused by CCP, with a high success rate and a very low incidence of complications.

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.

Implications of Kidney Disease in Patients with Peripheral Arterial Disease and Vascular Calcification

Persons with chronic kidney disease (CKD) are at a higher risk of developing peripheral artery disease (PAD) and its adverse health outcomes than individuals with normal renal function. Among patients with CKD, PAD is predominantly characterized by the calcification of the medial layer of arterial vessels in addition to intimal atherosclerosis and calcification. Vascular calcification (VC) is initiated by CKD-associated hyperphosphatemia, hypercalcemia, high concentrations of parathyroid hormone (PTH) as well as inflammation and oxidative stress. VC is widely prevalent in this cohort (>80% dialysis and 50% patients with CKD) and contributes to reduced arterial compliance and symptomatic peripheral arterial disease (PAD). The most severe form of PAD is critical limb ischemia (CLI) which has a substantial risk for increased morbidity and mortality. Percutaneous endovascular interventions with transluminal angioplasty, atherectomy, and intravascular lithotripsy are the current nonsurgical treatments for severe calcific plaque. Unfortunately, there are no randomized controlled trials that address the optimal approach to PAD and CLI revascularization in patients with CKD.

Histology, OCT, and Micro-CT Evaluation of Coronary Calcification Treated With Intravascular Lithotripsy: Atherosclerotic Cadaver Study

BACKGROUND

Although intravascular lithotripsy (IVL) has been an emerging novel option to treat vascular calcification, the specific effects on histology have not been systematically examined.

OBJECTIVES

The authors examined the histologic effects of IVL on coronary calcified lesions from human autopsy hearts and evaluated the diagnostic ability of optical coherence tomography (OCT) and micro-computed tomography (CT) to detect calcium fracture as identified by the gold standard histology.

METHODS

Eight coronary lesions were treated with IVL, and 7 lesions were treated with 10 atm inflation using an IVL catheter balloon without lithotripsy pulses (plain old balloon angioplasty [POBA]). OCT and micro-CT imaging were performed before and after treatment, and the presence of calcium fracture was assessed. The frequency and size of fractures were measured and compared with the corresponding histology.

RESULTS

All 15 treated lesions were diagnosed as sheet calcium by histology. Histological evidence of calcium fracture was significantly greater in the IVL group compared with the POBA group (62.5% vs 0.0%; P = 0.01). Calcified lesions with fracture had a larger maximum arc degree of calcification (median 145.6 [IQR: 134.4-300.4] degrees vs 107.0 [IQR: 88.9-129.1] degrees; P = 0.01). Micro-CT and histology showed an excellent correlation for fracture depth (R2 = 0.83; P < 0.0001), whereas OCT showed less correlation (R2 = 0.37; P = 0.11). The depth of fractures measured by OCT were significantly shorter than with those measured by histology (0.49 [IQR: 0.29-0.77] mm vs 0.88 [IQR: 0.64-1.07] mm; P = 0.008).

CONCLUSIONS

IVL demonstrated a histologically superior fracturing effect on coronary calcified lesions compared with POBA. OCT failed to identify the presence of some calcium fractures and underestimated the depth of fracture when compared with micro-CT.

Intravascular Lithotripsy for the Treatment of Severely Calcified Coronary Artery Disease: A DISRUPT CAD III Intravascular Ultrasound Substudy

BACKGROUND

Coronary intravascular lithotripsy (IVL) has emerged as a novel technique for the treatment of severely calcified coronary lesions. We evaluated the mechanism and efficacy of IVL in facilitating optimal stent implantation in heavily calcified coronary lesions using intravascular ultrasound (IVUS).

METHODS

Forty-six patients were initially enrolled as a part of the Disrupt CAD III study. Of these, 33 had pre-IVL, 24 had post-IVL, and 44 had post-stent IVUS evaluation. The final analysis was performed on 18 patients who had IVUS images interpretable at all three intervals. The primary endpoint was increase in minimum lumen area (MLA) from pre-IVL to post-IVL treatment to post-stenting.

RESULTS

Pre-IVL, MLA was 2.75 ± 0.84 mm2, percent area stenosis was 67.22 % ± 20.95 % with maximum calcium angle of 266.90° ± 78.30°, confirming severely calcified lesions. After IVL, MLA increased to 4.06 ± 1.41 mm2 (p = 0.0003), percent area stenosis decreased to 54.80 % ± 25.71 % (p = 0.0009), and maximum calcium angle decreased to 239.40° ± 76.73° (p = 0.003). There was a further increase in MLA to 6.84 ± 2.18 mm2 (p < 0.0001) and decrease in percent area stenosis to 30.33 % ± 35.08 % (p < 0.0001) post-stenting with minimum stent area of 6.99 ± 2.14 mm2. The success rate of stent delivery, implantation, and post-stent dilation was 100 % post-IVL.

CONCLUSION

In this first study evaluating the mechanism of IVL using IVUS, the primary endpoint of increase in MLA from pre-IVL to post-IVL treatment to post-stenting was successfully achieved. Our study showed that the use of IVL-assisted percutaneous coronary intervention is associated with improved vessel compliance, facilitating optimal stent implantation in de novo severely calcified lesions.

Shockwave Intravascular Lithotripsy Facilitated Transvenous Lead Extraction

BACKGROUND

Dense calcifications encasing pacing leads with long dwell times are common and increase the difficulty of and risks associated with transvenous lead extraction procedures (TLE). Shockwave intravascular lithotripsy (IVL) focuses sound waves to fracture calcified tissue within a narrow radius to the catheter.

OBJECTIVES

This study sought to assess the impact of Shockwave IVL pretreatment during extraction of long dwell time pacemaker and defibrillator leads.

METHODS

Data were compiled retrospectively from patients undergoing TLE at Essentia Health in Duluth, Minnesota, from October 2019 to April 2023. IVL pretreatment was performed using currently available 7- and 8-mm balloons with ≤300 pulses delivered in close proximity to the leads via a retrograde approach, after which the procedure was completed as usual.

RESULTS

Of the 120 patients undergoing TLE procedures, 55 were excluded from the study because the leads were freely mobile. Among the remaining 65 patients, 14 received IVL pretreatment. The median patient ages were similar at 67 (IQR: 63-76) years, with a lead dwell time of 10.7 (IQR: 6.9-14.9) years. The frequencies of diabetes, stroke, prior sternotomy, and lead types were not significantly different between the IVL and conventional groups. IVL pretreatment resulted in an average of 25 (IQR: 9-42) fewer minutes actively extracting leads (P = 0.007).

CONCLUSIONS

These data represent the first known cases using Shockwave IVL as an adjunctive measure during extraction of high-risk and high-complexity leads, with a resulting significant reduction in the amount of time spent engaging in the highest-risk phase of the procedure.

Mid-Term Angiographic and Intracoronary Imaging Results Following Intracoronary Lithotripsy in Calcified Coronary Artery Disease: Results From Two Tertiary Referral Centres

BACKGROUND

Intracoronary lithotripsy (IVL) is a safe and effective treatment for coronary calcification. Angiographic and intracoronary imaging follow-up have not yet been described. We aimed to describe the mid-term angiographic outcomes following IVL.

METHODS

Patients successfully treated with IVL in two tertiary referral hospitals were included. Repeat angiography and intracoronary imaging was performed. Quantitative coronary angiography (QCA) and optical coherence tomography (OCT) analyses were performed using dedicated workstations.

RESULTS

Twenty patients were included; mean age 67.1 years, left anterior descending artery 55 %. Median IVL balloon size was 3.0 mm and a median of 60 pulses were delivered per vessel. Percentage stenosis by QCA was 60 % [IQR 51-70] reducing to 20 % post stenting (p < 0.001). On OCT, 88.9 % had circumferential calcium. IVL resulted in fractures in 88.9 %. Resulting minimum stent expansion was 91.75 % [IQR 81.5-108]. Follow-up was at a median of 22.7 months [IQR16.4-25.5]. Percentage stenosis by QCA was 22.5 % [IQR 14-30] and not significantly different from the index procedure (p > 0.05). Minimum stent expansion by OCT was 85 % [IQR 72-97]. Late luminal loss was 0.15 mm [IQR -0.25 to 0.69]. Binary angiographic instent restenosis (ISR) was 10 % (2 of 20 patients). OCT demonstrated a predominantly homogenous neointimal pattern with high backscatter.

CONCLUSION

Following successful IVL treatment, repeat angiography demonstrated preserved stent parameters in the majority of patients with favorable vascular healing properties by OCT. A binary restenosis rate of 10 % was observed. These results suggest durable results following IVL treatment of severe coronary calcification however larger studies are warranted.

Sodium Chloride Physiological Saline Solution Versus Water Preparations Injectable in the Use of Shockwave Intravascular Lithotripsy: A Single-Center Experience

Background

Shockwave intravascular lithotripsy (IVL) coronary system is a very useful new technology for de novo severely calcified coronary artery plaques before percutaneous coronary intervention (PCI). The device uses a semi-compliant low-pressure balloon, integrated into a sterile catheter, to deliver by vaporizing fluid an expanding bubble that generates high-pressure ultrasonic energy by waves that create multiplane longitudinal micro-macro fractures in calcified plaques, which facilitate optimal stent placement and expansion, and luminal gain.

Methods

The use of Shockwave IVL coronary system in our cardiac catheterization laboratory (Cath lab) at the "Clinique Saint-Hilaire" in Rouen, France, started in March 2019, with 42 procedures performed since this date: two patients in 2019, two patients in 2020, seven patients in 2021, 23 patients in 2022, and eight patients since the beginning of 2023.

Results

We had experienced problems at the beginning of our activity for the first 11 patients (two patients in 2019, two patients in 2020, and seven patients in 2021): after less than five pulses, the shock therapy stopped. We used initially for Shockwave IVL semi-compliant low-pressure integrated balloons a mixture of 50% contrast and 50% water preparations injectable (PPI). After changing water PPI by sodium chloride physiological saline solution, we never encountered this problem again for the following 31 patients (23 patients in 2022, and eight patients since the beginning of 2023). In fact, the proper functioning of Shockwave IVL system requires ions in balloon mixture in addition to the contrast. It is thanks to the ions contained in sodium chloride physiological saline solution that the spark necessary for shocks delivery after balloon inflation is produced.

Conclusions

Water PPI or sodium chloride physiological saline solution is used in angioplasty balloons in a lot of Cath labs worldwide. It is therefore essential to disseminate in the worldwide Cath lab the obligation to put in Shockwave IVL semi-compliant low-pressure integrated balloons sodium chloride physiological saline solution, rather than water PPI for optimal performance, and the importance of Shockwave Medical reporting this to interventional cardiologists.

Randomized ComparIson of Strategies to PrepAre SeveRely CALCified Coronary Lesions 2: Design and Rationale of the ISAR-CALC 2 Trial

BACKGROUND

The percutaneous treatment of severely calcified coronary lesions has been associated with lower performance of coronary stents and poor clinical long-term outcomes. Adequate lesion preparation before stent implantation is of paramount importance to minimize the risk of stent failure. Balloon-based techniques for lesion preparation have been the subject of numerous investigations, albeit comparative data from randomized trials are scarce.

STUDY DESIGN AND OBJECTIVES

The ISAR-CALC 2 (ClinicalTrials.gov: NCT05072730) is an investigator-initiated, prospective, randomized, multicentre, assessors-blind, open-label trial designed to compare a lesion preparation strategy with either super high-pressure balloon or intravascular lithotripsy (IVL) before drug-eluting stent (DES) implantation in patients with severely calcified, undilatable coronary lesions. In total, 80 patients are required for trial completion. The primary endpoint will be final angiographic minimal lumen diameter (MLD) after stent implantation. Key secondary endpoints include stent expansion assessed by optical coherence tomography (OCT), procedural and strategy success, need for complementary lesion preparation with rotational atherectomy, acute lumen gain, and major adverse cardiac events up to 30-day follow-up.

CONCLUSIONS

The ISAR-CALC 2 trial aims to demonstrate the superiority of a lesion preparation strategy with a super high-pressure balloon as compared with intravascular lithotripsy prior to DES implantation in patients with severely calcified undilatable coronary lesions.

Barrier-breaking effects of ultrasonic cavitation for drug delivery and biomarker release

Recently, emerging evidence has demonstrated that cavitation actually creates important bidirectional channels on biological barriers for both intratumoral drug delivery and extratumoral biomarker release. To promote the barrier-breaking effects of cavitation for both therapy and diagnosis, we first reviewed recent technical advances of ultrasound and its contrast agents (microbubbles, nanodroplets, and gas-stabilizing nanoparticles) and then reported the newly-revealed cavitation physical details. In particular, we summarized five types of cellular responses of cavitation in breaking the plasma membrane (membrane retraction, sonoporation, endocytosis/exocytosis, blebbing and apoptosis) and compared the vascular cavitation effects of three different types of ultrasound contrast agents in breaking the blood-tumor barrier and tumor microenvironment. Moreover, we highlighted the current achievements of the barrier-breaking effects of cavitation in mediating drug delivery and biomarker release. We emphasized that the precise induction of a specific cavitation effect for barrier-breaking was still challenged by the complex combination of multiple acoustic and non-acoustic cavitation parameters. Therefore, we provided the cutting-edge in-situ cavitation imaging and feedback control methods and suggested the development of an international cavitation quantification standard for the clinical guidance of cavitation-mediated barrier-breaking effects.

Intravascular lithotripsy angioplasty for treatment of atherosclerotic coral-reef occlusion of the infrarenal aorta and its bifurcation

In the present report, we have described the use of intravascular lithotripsy angioplasty for heavily calcified occlusions of the infrarenal aorta and its bifurcation in two patients. In the first patient, two lithotripsy balloons in kissing conformation were simultaneously used to allow for dilatation of the distal aorta and its bifurcation with preservation of accessory renal artery patency, followed by stenting of the iliac arteries. For the second patient, the infrarenal aorta occlusion was first treated with a single lithotripsy balloon, followed by covered stenting. Intravascular lithotripsy could represent a valid endovascular adjunct to optimize outcomes in the treatment of coral reef aortas and aortic bifurcation occlusion.

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.

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.

Bail out lithotripsy to treat delayed valve-in-valve TAVR-related coronary obstruction

Coronary access difficulty and stent compression by the juxtaposed aortic valve leaflet hamper percutaneous management of delayed coronary artery obstruction (CAO) after valve-in-valve (Edwards Sapien 3 in St. Jude Trifecta) transcatheter aortic valve replacement (TAVR). Here, we present a case of delayed post-TAVR CAO treated with intravascular lithotripsy and multistenting to overcome stent compression by the adjacent calcified leaflet.

Use of Intravascular Lithotripsy in Heavily Calcified Renal Artery Stenosis: A Case Report

Heavily calcified arterial lesions are difficult to treat in an endovascular manner with conventional techniques due to limited arterial compliance. Intravascular lithotripsy offers a novel minimally invasive therapeutic option through endovascular emission of acoustic waves, fracturing calcium deposits and facilitating lesion dilation. We present the case of a successful application of the Shockwave intravascular lithotripsy system (IVL®, Shockwave Medical Inc) in a heavily calcified stenosis of the right renal artery in a patient with a coral reef aorta.

Microfracture Augmentation With Direct In Situ Radial Shockwave Stimulation With Appropriate Energy Has Comparable Repair Performance With Tissue Engineering in the Porcine Osteochondral Defect Model

BACKGROUND

The first-line clinical strategy for small cartilage/osteochondral defects is microfracture (MF). However, its repair efficacy needs improvement.

HYPOTHESIS

Appropriate energy radial shockwave stimulation in MF holes would greatly improve repair efficacy in the porcine osteochondral defect model, and it may obtain comparable performance with common tissue engineering techniques.

STUDY DESIGN

Controlled laboratory study.

METHODS

Osteochondral defect models (8-mm diameter, 3-mm depth) were established in the weightbearing area of Bama pigs' medial femoral condyles. In total, 25 minipigs were randomly divided into 5 groups: control (Con; without treatment), MF, MF augmentation (MF+; treated with appropriate energy radial shockwave stimulation in MF holes after MF), tissue engineering (TE; treated with compounds of microcarrier and bone marrow mesenchymal stem cells), and sham (as the positive control). After 3 months of intervention, osteochondral specimens were harvested for macroscopic, radiological, biomechanical, and histological evaluations. The statistical data were analyzed using 1-way analysis of variance.

RESULTS

Based on the macroscopic appearance, the smoothness and integration of the repaired tissue in the MF+ group were improved when compared with the Con and MF groups. The histological staining suggested more abundant cartilaginous matrix deposition in the MF+ group versus the Con and MF groups. The general scores of the macroscopic and histological appearances were comparable in the MF+ and the TE groups. The high signal areas of the osteochondral unit in the magnetic resonance images were significantly decreased in the MF+ group, with no difference with the TE group. The micro-computed tomography data demonstrated the safety of direct in situ radial shockwave performance. Biomechanical tests revealed that the repaired tissue's Young modulus was highest in the MF+ group and not statistically different from that in the TE group.

CONCLUSION

Direct in situ radial shockwave stimulation with appropriate energy significantly improves the short-term repair efficacy of MF. More encouragingly, the MF+ group in our study obtained repair performance comparable with the TE therapy.

CLINICAL RELEVANCE

This strategy is easy to perform and can readily be generalized with safety and higher cartilage repair efficacy. Moreover, it is expected to be accomplished under arthroscopy, indicating tremendous clinical transformative value.

Intravascular Lithotripsy for Treatment of Calcified Coronary Artery Disease

Intravascular lithotripsy (IVL) uses acoustic shock waves in a balloon-based delivery system to modify severely calcified atherosclerotic coronary vascular lesions in preparation for stent implantation. IVL results in circumferential and longitudinal calcium fracture, which improves transmural vessel compliance and facilitates subsequent stent expansion without requiring high-pressure balloon dilation. Clinical trials have demonstrated IVL to be safe (low rates of major adverse cardiac events in hospital and to 1 year; low rates of severe angiographic complications), effective (high rates of procedural success), and easy to use (little or no learning curve) when applied in the treatment of severely calcified coronary arteries.

Intravascular lithotripsy for coronary calcium: A case report and review of the literature

BACKGROUND

Coronary calcium poses a challenge for the interventional cardiologist often leading to stent under-expansion and subsequent ischemic events. Aggressive balloon post-dilatation though helpful is usually inadequate. Multiple plaque ablation techniques are in vogue, but they are technically demanding and are not without complications. Shockwave intravascular lithotripsy (S-IVL) has emerged as a user-friendly and effective mechanism for calcium management with a high safety margin. A series of trials (DISRUPT CAD I-IV) have demonstrated both short-term and long-term safety and efficacy of the technique. As experience with the technique grows more and more, therapy areas like stent restenosis are being covered by the S-IVL.

CASE SUMMARY

We report a series of 2 cases successfully managed with S-IVL therapy at our center. The first case is of a 57-year-old smoker who presented with acute coronary syndrome. His left anterior descending coronary artery revealed calcified 90% stenosis on angiogram and a combination of superficial-deep calcium on intracoronary imaging. The calcium was treated with 20 pulses of S-IVL to create discontinuity and a sirolimus eluting drug-eluting stent was successfully implanted. The second case is that of an elderly lady who presented with stable angina and demonstrated diffuse calcified lesions in the left anterior descending artery on angiogram. She also demonstrated a mixture of superficial and deep seated calcium zones on imaging. S-IVL therapy was applied to generate fractures in calcium, and two overlapping drug-eluting stents were implanted successfully without any complications.

CONCLUSION

S-IVL is an emerging, efficient, user-friendly and safe therapy for managing intracoronary calcium in routine interventional practice.

In Vitro Model for the Evaluation of Innovative Transcatheter Debridement Device (TDD): Pericardium-Based Scaffold and Stem Cells to Reproduce Calcificated Valves

Aortic valve stenosis has become the most common valvular disease in elderly patients. Several treatments are available such as surgical aortic valve replacement and transcatheter aortic valve implantation. To date, however, there is a need to discover alternative treatments that can delay the disease progression and, therefore, the implant of a prosthetic valve. In this regard, a decalcification procedure based on the use of ultrasonic waves could represent an innovative solution in transcatheter cardiovascular therapies. In this article, we describe an innovative transcatheter debridement device (TDD) that uses low-intensity ultrasound shock waves for calcium ablation from the native aortic valve and bioprosthetic valve. Mesenchymal stem cells were seeded onto pericardium-based scaffolds and committed into an osteogenic phenotype. After treatment with TDD, cell proliferation was analyzed, as well as lactate dehydrogenase release and cell morphology. The release of calcium and inflammation events were detected. The results confirmed that the TDD was able to induce a safe decalcification without any adverse inflammatory events.

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.

Guidezilla™ guide extension catheter I for transradial coronary intervention

Background

Percutaneous coronary intervention (PCI) is the preferred treatment method for coronary artery diseases (CAD). This study aimed to evaluate the effectiveness and complications of the Guidezilla™ guide extension catheter I (GGEC I) in transradial coronary intervention (TRI).

Methods

This case series study included patients with CAD who underwent TRI using the GGEC I between August 2016 and January 2019 at the First Affiliated Hospital of Xi'an Jiaotong University.

Results

A total of 221 patients aged 65.1 ± 9.26 years were included. Coronary angiography results indicated that most patients (77.8%) had triple-vessel lesions, including 47.5% with chronic total occlusion (CTO). A total of 237 target lesions were treated, most being type C lesions (95.8%). The most common indication for GGEC I use was heavy calcification (67%), followed by extreme tortuosity (12.2%), extreme tortuosity and heavy calcification (10.9%), distally located lesion (4.5%), picking up the retrograde wire (3.2%), anomalous vessel origin (1.8%), and releasing the burr incarceration (0.4%). The mean operation time was 58 min, and the overall success rate was 94.1%. Four patients received a drug-coated balloon. No significant differences were found in operation time and success rate among the low (<23), intermediate (23-32), and severe (>32) CAD groups based on SYNTAX score stratification (P > 0.05). Two subacute thrombosis cases each were reported perioperatively, during hospitalization, and at the 1-month follow-up.

Conclusion

The GGEC I might have advantages for TRI and is unaffected by SYNTAX score stratification.

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.

Intravascular Lithotripsy for the Treatment of Stent Underexpansion: The Multicenter IVL-DRAGON Registry

Background: Whereas the efficacy and safety of intravascular lithotripsy (IVL) have been confirmed in de novo calcified coronary lesions, little is known about its utility in treating stent underexpansion. This study aimed to investigate the impact of IVL in treating stent underexpansion. Methods and Results: Consecutive patients with stent underexpansion treated with IVL entered the multicenter IVL-Dragon Registry. The procedural success (primary efficacy endpoint) was defined as a relative stent expansion >80%. Thirty days device-oriented composite endpoint (DOCE) (defined as a composite of cardiac death, target lesion revascularization, or target vessel myocardial infarction) was the secondary endpoint. A total of 62 patients were enrolled. The primary efficacy endpoint was achieved in 72.6% of patients. Both stent underexpansion 58.5% (47.5−69.7) vs. 11.4% (5.8−20.7), p < 0.001, and the stenotic area 82.6% (72.4−90.8) vs. 21.5% (11.1−37.2), p < 0.001, measured by quantitative coronary angiography improved significantly after IVL. Intravascular imaging confirmed increased stent expansion following IVL from 37.5% (16.0−66.0) to 86.0% (69.2−90.7), p < 0.001, by optical coherence tomography and from 57.0% (31.5−77.2) to 89.0% (85.0−92.0), p = 0.002, by intravascular ultrasound. Secondary endpoint occurred in one (1.6%) patient caused by cardiac death. There was no target lesion revascularization or target vessel myocardial infarction during the 30-day follow-up. Conclusions: In this real-life, largest-to-date analysis of IVL use to manage underexpanded stent, IVL proved to be an effective and safe method for facilitating stent expansion and increasing luminal gain.

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.