Coronary Calcification and Long-Term Outcomes According to Drug-Eluting Stent Generation

Comparison of intravascular lithotripsy versus rotational atherectomy for the treatment of severe coronary artery calcification

BACKGROUND

Calcified lesions are one of the most challenging cases for PCI, where optimal angiographic results and satisfying outcomes are hard to achieve.

METHODS

We evaluated the baseline clinical, procedures characteristics and outcomes of patients with severe coronary artery calcification (CAC) who underwent coronary intravascular lithotripsy (IVL) and rotational atherectomy (RA).

RESULTS

Respectively 152 and 238 patients who underwent IVL and RA are enrolled from January 2023 to November 2023. Regarding demographic characteristics, the gender proportion, medical history of PCI and smoke history among groups reach statistical significance. Left anterior descending and right coronary artery were the main vessels treated in both groups. The 2.5 and 3.0 mm IVL balloons and 1.5 mm burr were the most commonly used. 99.3% cases were successfully implanted drug-eluting stents after IVL balloon pre-treatment, which was higher than in the group treated with RA. During hospitalization, there were no serious adverse events in the IVL group, but there were two adverse events in the RA group. Procedural complications were higher in the RA group than the IVL group (5.5% vs. 0.7%, P = 0.027).

CONCLUSIONS

IVL appears to be safe and effective for the treatment of severe CAC lesions compared to RA.

Drug-Eluting Balloons in Calcified Coronary Lesions: A Meta-Analysis of Clinical and Angiographic Outcomes

Background: The usefulness of drug-eluting balloons (DEBs) has not been fully elucidated in calcified coronary lesions (CCLs). This meta-analysis aimed to evaluate the efficacy of DEBs compared to a drug-eluting stent (DES) in this setting. Methods: PubMed, EMBASE and Cochrane were searched through December 2023. The primary endpoint was 12 months major adverse cardiac events (MACE). Secondary endpoints included clinical outcomes and angiographic results after PCI and at a 12-month follow-up. Results: Five studies and a total of 1141 patients with 1176 coronary lesions were included. Overall, the DEB was comparable to DES in MACE (RR = 0.86, 95% CI: 0.62-1.19, p = 0.36), cardiac death (RR = 0.59, 95% CI: 0.23-1.53, p = 0.28), myocardial infarction (RR = 0.89, 95% CI: 0.25-3.24, p = 0.87) and target lesion revascularization (RR = 1.1, 95% CI: 0.68-1.77, p = 0.70). Although the DEB was associated with worse acute angiographic outcomes (acute gain; MD = -0.65, 95% CI: -0.73, -0.56 and minimal lumen diameter; MD = -0.75, 95% CI: -0.89, -0.61), it showed better results at 12 months follow-up (late lumen loss; MD = -0.34, 95% CI: -0.62, -0.07). Conclusions: This meta-analysis showed that the DEB strategy is comparable to DES in the treatment of CCLs in terms of clinical outcomes. Although the DEB strategy had inferior acute angiographic results, it may offer better angiographic results at follow-up.

Coronary artery calcification: concepts and clinical applications

Vascular calcification is an important hallmark of atherosclerosis. Coronary artery calcification (CAC) implies the presence of coronary artery disease (CAD), irrespective of risk factors or symptoms, is concomitant with the development of advanced atherosclerosis. Coronary thrombosis is the most common clinical end event leading to acute coronary syndrome (ACS). The least common type of pathology associated with thrombosis is the calcified nodule (CN). It usually occurs in elderly patients with severely calcified and tortuous arteries. The prevalence of calcified nodules in patients with ACS may be underestimated due to the lack of easily recognisable diagnostic methods. In this review, the authors will focus on the classification, clinical significance, pathogenesis, and diagnostic evaluation and treatment of CAC to further explore the clinical significance of CN.

Serial longitudinal changes of coronary calcified plaques with clear outer borders under intensive lipid management: insights from optical coherence tomography

Percutaneous coronary intervention (PCI) for calcified lesions is one of the most challenging procedures related to worse clinical outcomes. To stabilize vulnerable plaques, intensive lipid management is recommended; however, the serial changes of calcified plaques under intensive lipid management are unknown. A total of 31 patients (mean age, 63 ± 10 years; men, 29 patients) who underwent PCI with intensive lipid management were retrospectively studied. We evaluated the serial longitudinal changes of calcified plaques with clear outer borders using optical coherence tomography (OCT) at two time points: at the time of PCI (baseline) and the chronic phase. The median interval from PCI to chronic phase was 287 (233-429) days. Twenty-eight patients (90.3%) had increased calcium volume at the chronic phase compared with those at baseline (2.6 [1.3-5.1] vs. 1.8 [0.7-4.3] mm2, p < 0.05), and the median increase rate of calcium volume was 27.4% at the chronic phase. According to the median increase rate of calcium volume (27.4%), patients were divided into the following two groups: rapid progression (≥ 27.4%, RP group) and non-rapid progression (< 27.4%, non-RP group). The RP group had more patients with diabetes, and diabetes was independently associated with rapid progression by multivariate analysis. Furthermore, patients with diabetes had significantly higher changes in calcium index and volume from the baseline to the chronic phase than those without diabetes. Coronary calcification progression during relatively short intervals was observed using OCT even under intensive lipid management. Diabetes was an independent predictor for rapid coronary calcification progression.

A Prospective, Multicenter, Real-World Registry of Coronary Lithotripsy in Calcified Coronary Arteries: The REPLICA-EPIC18 Study

BACKGROUND

Intravascular lithotripsy (IVL) has demonstrated effectiveness in the treatment of calcified lesions in selected patients with stable coronary disease.

OBJECTIVES

The authors sought to assess the performance of coronary IVL in calcified coronary lesions in a real-life, all comers, setting.

METHODS

The REPLICA-EPIC18 study prospectively enrolled consecutive patients treated with IVL in 26 centers in Spain. An independent core laboratory performed the angiographic analysis and event adjudication. The primary effectiveness endpoint assessed procedural success (successful IVL delivery, final diameter stenosis <20%, and absence of in-hospital major adverse cardiovascular events [MACE]). The primary safety endpoint measured freedom from MACE at 30 days. A predefined substudy compared outcomes between acute coronary syndrome (ACS) and chronic coronary syndrome (CCS) patients.

RESULTS

426 patients (456 lesions) were included, 63% of the patients presenting with ACS. IVL delivery was successful in 99% of cases. Before IVL, 49% of lesions were considered undilatable. The primary effectiveness endpoint was achieved in 66% of patients, with similar rates among CCS patients (68%) and ACS patients (65%). Likewise, there were no significant differences in angiographic success after IVL between CCS and ACS patients. The rate of MACE at 30 days (primary safety endpoint) was 3% (1% in CCS and 5% in ACS patients [P = 0.073]).

CONCLUSIONS

Coronary IVL proved to be a feasible and safe procedure in a "real-life" setting, effectively facilitating stent implantation in severely calcified lesions. Patients with ACS on admission showed similar angiographic success rates but showed a trend toward higher 30-day MACE compared with patients with CCS. (REPLICA-EPIC18 study [Registry of Coronary Lithotripsy in Spain]; NCT04298307).

Tissue responses to everolimus-eluting stents implanted in severely calcified lesions following atherectomy

Histopathological examination has revealed that stents on severely calcified plaques were associated with delayed vascular healing. Although atherectomy devices can increase the number of malapposed struts, tissue responses to implanted drug eluting stents in atherectomy patients remain largely unknown. This retrospective observational study included 30 patients who underwent atherectomy and everolimus-eluting stent (EES) deployment for severely calcified coronary lesions (biodegradable polymer EES (BP-EES), n = 15; durable polymer EES (DP-EES), n  = 15). Optical coherence tomography was carried out at baseline and follow-up, and struts with acute stent malapposition (ASM) were categorized as struts on modified calcium (mod-Ca), non-modified calcium (non-mod-Ca), or non-calcium (non-Ca). Adequate vascular healing, defined as ASM resolution with neointimal coverage, was compared between the BP-EES and DP-EES groups. Multivariate linear regression analysis using a generalized estimated equation revealed that BP-EES use was associated with significantly better adequate vascular healing compared with DP-EES (odds ratio [OR]: 3.691, 95% confidence interval [CI] 1.175-11.592, P = 0.025). adequate vascular healing was associated with the underlying plaque morphology (mod-Ca vs non-mod-Ca: OR 2.833, 95% CI 1.491-5.384, P = 0.001; non-Ca vs non-mod-Ca: OR 1.248, 95% CI 0.440-3.543, P = 0.677). This study demonstrates that drug-eluting stent selection and calcium modification are possible factors affecting vascular healing of malapposed struts in severely calcified lesions.

Rotational atherectomy combined with cutting balloon to optimise stent expansion in calcified lesions: the ROTA-CUT randomised trial

BACKGROUND

Percutaneous coronary intervention (PCI) of calcified lesions remains challenging for interventionalists.

AIMS

We aimed to investigate whether combining rotational atherectomy (RA) with cutting balloon angioplasty (RA+CBA) results in more optimal stent expansion compared with RA followed by non-compliant balloon angioplasty (RA+NCBA).

METHODS

ROTA-CUT is a prospective, multicentre, randomised trial of 60 patients with coronary artery disease undergoing PCI of moderately or severely calcified lesions with drug-eluting stent implantation. Patients were randomised 1:1 to either RA+CBA or RA+NCBA. The primary endpoint was the minimum stent area on intravascular ultrasound (IVUS). Secondary endpoints included minimum lumen area and stent expansion assessed by IVUS and acute lumen gain, final residual diameter stenosis and minimum lumen diameter assessed by angiography. Clinical endpoints were obtained at 30 days.

RESULTS

The mean age was 71.1±9.4 years, and 22% were women. The procedural details of RA were similar between groups, as were procedure duration and contrast use. Minimum stent area was similar with RA+CBA versus RA+NCBA (6.7±1.7 mm2 vs 6.9±1.8 mm2; p=0.685). Furthermore, there were no significant differences regarding the other IVUS and angiographic endpoints. Procedural complications were rare, and 30-day clinical events included 2 myocardial infarctions and 1 target vessel revascularisation in the RA+CBA group and 1 myocardial infarction in the RA+NCBA group.

CONCLUSIONS

Combining RA with CBA resulted in a similar minimum stent area compared with RA followed by NCBA in patients undergoing PCI of moderately or severely calcified lesions. RA followed by CBA was safe with rare procedural complications and few clinical adverse events at 30 days.

Impact of atherothrombotic risk stratification in patients with heavily calcified lesions following rotational atherectomy

BACKGROUND

Patients who undergo percutaneous coronary intervention (PCI) with rotational atherectomy (RA) are at high risk of adverse clinical outcomes, and there are few clinical risk stratification tools for these patients.

METHODS

We conducted a study with 196 patients who underwent PCI with RA out of 7391 patients who underwent PCI using a multicenter, prospective cohort registry. Patients were divided into three groups according to the tertiles of the Thrombolysis in Myocardial Infarction (TIMI) Risk Score for Secondary Prevention (TRS 2°P): 65 patients in the T1 group (TRS 2°P < 3), 66 patients in the T2 group (TRS 2°P = 3), and 65 patients in the T3 group (TRS 2°P > 3). The primary endpoint was the cumulative 2-year incidence of major adverse cardiovascular and cerebrovascular events (MACCE), defined as a composite of cardiac death, acute coronary syndrome, and ischemic stroke.

RESULTS

Cumulative 2-year MACCE occurred in 41 patients (24 %) during the follow-up period. The cumulative incidence of MACCE was significantly higher in the T3 group than in the T1 group (log-rank test, p = 0.02). Multivariate Cox analyses revealed that the T3 group was associated with an increased risk of MACCE compared to that of the T1 group (adjusted hazard ratio, 2.66; 95 % confidence interval, 1.04-6.77; p = 0.04). The addition of TRS 2°P to conventional risk factors, including male sex, number of diseased vessels, and low-density lipoprotein cholesterol levels, improved the net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.39, p = 0.027; IDI 0.072, p < 0.001).

CONCLUSIONS

Atherothrombotic risk stratification using TRS 2°P was useful in identifying high-risk patients with heavily calcified lesions following RA.

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.

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.

Modified balloons to prepare severely calcified coronary lesions before stent implantation: a systematic review and meta-analysis of randomized trials

BACKGROUND

The performance of modified balloons (namely cutting or scoring balloons) to prepare severely calcified lesions in patients undergoing percutaneous coronary intervention (PCI) remains controversial. We investigated the clinical and imaging outcomes of patients undergoing PCI assigned to modified balloon therapy to prepare severely calcified coronary lesions before stent implantation.

METHODS

In this meta-analysis, we aggregated the study-level data from trials enrolling invasively treated patients who were randomly assigned to modified balloon or control therapy to prepare severely calcified lesions before stenting. The primary outcome was major adverse cardiac events (MACE), including death, myocardial infarction (MI), and repeat revascularization. The secondary outcomes included the individual components of the primary outcome, coronary perforation and final minimal stent area (MSA) as measured by intracoronary imaging.

RESULTS

A total of 648 participants in six trials were allocated to modified balloon therapy (n = 335) or control therapy (semi-compliant, non-compliant, or super high-pressure balloon, n = 313). The median follow-up was 11 months. Overall, MACE occurred in 8.96% of patients assigned to a modified balloon and 12.78% of patients assigned to control therapy [risk ratio = 0.70, 95% confidence interval (CI) 0.35-1.39; P = 0.24]. There was a significant treatment effect-by-modified balloon type interaction for the outcome MACE in patients assigned to cutting balloon compared with control therapy [RR = 0.40 (0.28-0.56), P for interaction (Pint) < 0.001]. Patients treated with a modified balloon compared with control therapy showed neither a significant difference for the other clinical outcomes nor for final MSA [standardized mean difference = 0.67 (- 0.71, 2.06); P = 0.26].

CONCLUSIONS

In patients treated with PCI for severely calcific coronary artery disease a strategy of lesion preparation with a modified balloon before stenting does not improve clinical or imaging outcomes compared with control therapy. The different performance of cutting and scoring balloons warrants further investigation.

Secondary rotational atherectomy is associated with reduced occurrence of prolonged ST-segment elevation following ablation

Elevation of the ST segment after percutaneous coronary intervention (PCI) using rotational atherectomy (RA) for severely calcified lesions often persists after disappearance of the slow-flow phenomenon on angiography. We investigated clinical factors relevant to prolonged ST-segment elevation following RA among 152 patients with stable angina undergoing elective PCI. PCI procedures were divided into two strategies, RA without (primary RA strategy) or with (secondary RA strategy) balloon dilatation before RA. Incidence of prolonged ST-segment elevation after disappearance of slow-flow phenomenon was higher in the 56 patients with primary RA strategy (13%) than in the 96 patients with secondary RA strategy (3%, p = 0.039). Univariate logistic regression analysis showed levels of low-density lipoprotein cholesterol (LDL-C) (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.93-0.99; p = 0.013), levels of triglycerides (OR 0.97, 95%CI 0.94-0.99; p = 0.040), and secondary RA strategy (OR 0.23, 95% CI 0.05-0.85; p = 0.028) were inversely associated with occurrence of prolonged ST-segment elevation following ablation. However, hemodialysis, diabetes mellitus, left-ventricular ejection fraction, lesion length ≥ 20 mm, and burr size did not show significant associations. Multivariate logistic regression analysis modeling revealed that secondary RA strategy was significantly associated with the occurrence of prolonged ST-segment elevation (Model 1: OR 0.24, 95% CI 0.05-0.95, p = 0.042; Model 2: OR 0.17, 95% CI 0.03-0.68, p = 0.018; Model 3: OR 0.21, 95% CI 0.03-0.87, p = 0.041) even after adjusting for levels of LDL-C and triglycerides. Secondary RA strategy may be useful to reduce the occurrence of prolonged ST-segment elevation following RA.

Lifetime management of severely calcified coronary lesions: the treatment algorithm focused on the shape of calcification

The concept of lifetime management has not been discussed in the field of percutaneous coronary intervention (PCI), because the durability of drug-eluting stent (DES) is considered to be long enough for most patients. Furthermore, even if in-stent restenosis occurs, the treatment for in-stent restenosis is simple in most cases. On the other hand, the long-term clinical outcomes after DES implantation are worse in severely calcified coronary lesions than in non-calcified lesions. Moreover, the treatment for in-stent calcified restenosis or restenosis due to stent underexpansion is not simple. The concept of lifetime management of severely calcified lesions may be necessary like that of aortic stenosis. Recently, several algorithms have been published in PCI to severely calcified lesions, partly because of the emergence of IVL. These algorithms focus on the selection of cracking and debulking devices for the preparation of stenting. However, the optimal stent expansion does not guarantee the long-term patency, when the target lesion includes calcified nodules. Stent restenosis due to calcified nodules is difficult to manage. In this review article, we propose the algorithm for severely calcified lesions focused on the shape of calcification. We do not need to hesitate stenting when multiple cracks on circumferential calcification are observed by intravascular imaging devices. However, DCB may be an option as final device in some situations, when lifetime management of severely calcified lesions is considered.

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.

The Usefulness of Intracoronary Imaging in Patients with ST-Segment Elevation Myocardial Infarction

Intracoronary imaging (ICI) modalities, namely intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have shown to be able to reduce major adverse cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). Nevertheless, patients with ST-segment elevation myocardial infarction (STEMI) have been practically excluded from contemporary large randomized controlled trials. The available data are limited and derive mostly from observational studies. Nevertheless, contemporary studies are in favor of ICI utilization in patients who undergo primary PCI. Regarding technical aspects of PCI, ICI has been associated with the implantation of larger stent diameters, higher balloon inflations and lower residual in-stent stenosis post-PCI. OCT, although used significantly less often than IVUS, is a useful tool in the context of myocardial infarction without obstructive coronary artery disease since, due to its high spatial resolution, it can identify the underlying mechanism of STEMI, and, thus, guide therapy. Stent thrombosis (ST) is a rare, albeit a potential lethal, complication that is expressed clinically as STEMI in the vast majority of cases. Use of ICI is encouraged with current guidelines in order to discriminate the mechanism of ST among stent malapposition, underexpansion, uncovered stent struts, edge dissections, ruptured neoatherosclerotic lesions and coronary evaginations. Finally, ICI has been proposed as a tool to facilitate stent deferring during primary PCI based on culprit lesion characteristics.

Shock and Awe: Successful Revascularization with Intravascular Lithotripsy in Recurrent ST-Elevation Myocardial Infarction Secondary to Stent Under-Expansion

We report a case of recurrent ST-segment elevation myocardial infarction (STEMI) due to a previously implanted under-expanded stent with in-stent thrombosis refractory to traditional interventional techniques. We underscore the utility of bail-out shockwave intravascular lithotripsy to tackle previously under-expanded stents in this acute setting.

The Supportive Guidewire Paradox: How Extra Support Guidewires May Hinder Equipment Delivery Through Tortuous and Calcified Coronary Lesions

Percutaneous coronary intervention of heavily calcified coronary vessels can be challenging due to difficult equipment delivery and suboptimal stent expansion, leading to worse clinical outcomes. Supportive guidewires are designed to facilitate equipment delivery. We present two cases of heavily calcified and tortuous coronary lesions in which use of support guidewires hindered balloon and stent delivery, possibly by increasing friction between equipment and the wall of the coronary vessel. Equipment delivery was achieved using less supportive workhorse guidewires.

The Role of Intracoronary Imaging for the Management of Calcified Lesions

Interventional cardiologists in everyday practice are often confronted with calcified coronary lesions indicated for percutaneous transluminal coronary angioplasty (PTCA). PTCA of calcified lesions is associated with diverse technical challenges resulting in suboptimal coronary stenting and adverse long-term clinical outcomes. Angiography itself offers limited information regarding coronary calcification, and the adjuvant use of intracoronary imaging such as intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) can guide the treatment of calcified coronary lesions, optimizing the different stages of the procedure. This review offers a description of why, when, and how to use intracoronary imaging for PTCA of calcified coronary lesions in order to obtain the most favorable results. We used the PubMed and Google Scholar databases to search for relevant articles. Keywords were calcified coronary lesions, intracoronary imaging, IVUS, OCT, coronary calcium modification techniques, PTCA, and artificial intelligence in intracoronary imaging. A total of 192 articles were identified. Ninety-one were excluded because of repetitive or non-important information.

Intravascular Ultrasound Guided Intervention in Calcified Coronary Lesions Showed Good Clinical Outcomes during One Year Follow-Up

BACKGROUND

Calcified coronary lesions can cause stent under-expansion, malapposition, and polymer degradation, hence increasing the risk of adverse clinical outcomes. Percutaneous coronary intervention (PCI) guided by intravascular ultrasound (IVUS) has been used regularly to improve outcomes. Our primary aim was to evaluate the clinical efficacy of IVUS-guided PCI in calcified coronary lesions.

METHODS

From August 2018 to December 2021, we prospectively included 300 patients in the CAPIRO study (CAlcified plaque in patients receiving Resolute Onyx^®) at three educational hospitals in Jeonbuk Province. We studied 243 patients (265 lesions) who were followed up for over a year. Based on coronary calcification by IVUS analysis, the patient population was categorized into two groups (Group I: non/mild calcification; Group II: moderate/severe calcification (maximum calcium arc >180° and calcium length > 5 mm)). One-to-one Propensity Score Matching was used to match the baseline characteristics. The stent expansion rate was analyzed by recent criteria. The primary clinical outcome was Major Adverse Cardiac Events (MACE), which included Cardiac death, Myocardial Infarction (MI), and Target Lesion Revascularization (TLR).

RESULTS

After follow-up time, the MACE rate in Group I was 1.99%, comparable to Group II's 1.09% (p = 0.594). The components of MACE did not significantly differ between the two groups. Based on absolute MSA or MSA/MVA at MSA site criteria, the stent expansion rate in Group II was lower than that of Group I. Nevertheless, based on recent relative criteria, the stent expansion rate in both groups was comparable.

CONCLUSIONS

After more than a year of follow-up, IVUS-guided PCI in moderate/severe calcification lesions was associated with good clinical outcomes, which was comparable with non/mild calcification lesions. Future studies with a larger sample size and a more extended follow-up period are required to clarify our findings.

Long-term outcomes of drug-coated balloon treatment of calcified coronary artery lesions: a multicenter, retrospective, propensity matching study

Background

Coronary artery calcification (CAC) is associated with high rates of restenosis and adverse clinical events after percutaneous coronary intervention (PCI) with drug-eluting stents (DES).

Objectives

The aim of this study was to evaluate the long-term clinical outcomes of drug-coated balloon (DCB)-only treatment for de novo lesions with and without CAC.

Methods

Patients with de novo coronary disease treated with the DCB-only strategy were retrospectively enrolled from three centers and categorized into a CAC group and a non-CAC group. The primary endpoint was the target lesion failure (TLF) rate during the 3-year follow-up. Secondary endpoints included the occurrence of major adverse cardiac events (MACEs), target lesion revascularization (TLR), cardiac death, myocardial infarction (MI) and any revascularization. Propensity score matching (PSM) was conducted to assemble a cohort of patients with similar baseline characteristics.

Results

A total of 1,263 patients with 1,392 lesions were included, and 243 patients were included in each group after PSM. Compared with the non-CAC group, the incidence rates of TLF (9.52% vs. 4.94%, odds ratio [OR]: 2.080; 95% confidence interval [CI]: 1.083-3.998, P = 0.034) and TLR (7.41% vs. 2.88%, OR: 2.642; 95% CI: 1.206-5.787, P = 0.020) in the CAC group were higher. The incidence rates of MACE (12.35% vs. 7.82%, OR: 1.665; 95% CI: 0.951-2.916, P = 0.079), cardiac death (2.06% vs. 2.06%, OR: 0.995; 95% CI: 0.288-3.436, P = 0.993), MI (1.23% vs. 0.82%, OR: 2.505; 95% CI: 0.261-8.689, P = 0.652) and any revascularization (12.76% vs. 9.67%, OR: 1.256; 95% CI: 0.747-2.111, P = 0.738) were similar between groups.

Conclusions

CAC increased the incidence of TLF and TLR without a substantial increase in the risk of MACE, cardiac death, MI, or any revascularization in patients treated with DCB-only angioplasty during the 3-year follow-up.

Comparison of long-term outcome in patients with calcified stenosis treated with intravascular lithotripsy or with modified balloon angioplasty: a propensity score-adjusted study

Background

The aim of this two-center, all-comers registry was to compare the effectiveness and safety of intravascular lithotripsy (IVL) to that of modified balloon angioplasty (MB). MB angioplasty using a cutting or scoring balloon is commonly used in patients with calcified coronary arteries. IVL is a new technology for lesion preparation. This is the first study to compare MB with IVL.

Methods

The cohort included all patients treated by MB angioplasty or IVL between 2019 and 2021. The primary endpoint was strategy success (<20% residual stenosis). The secondary endpoint was long-term safety outcomes [cardiac death, acute myocardial infarction (AMI), target lesion failure/revascularization (TVR)]. Quantitative coronary angiography (QCA) was performed in all patients. Primary and secondary endpoints were compared using inverse probability of treatment weighting (IPTW) for treatment effect estimation.

Results

A total of n = 86 patients were treated by IVL and n = 92 patients by MB angioplasty. The primary endpoint was reached in 152 patients (85.4%). Patients in the IVL group had less residual stenosis (5.8% vs. 22.8%; p = 0.001) in QCA. Weighted multivariable regression analysis revealed that IVL had a significant positive effect on reaching the primary endpoint of strategy success [odds ratio (OR) 24.58; 95% confidence interval (95% CI) 7.40-101.86; p = 0.001]. In addition, severe calcification was shown to result in a lower probability of achieving the primary endpoint (OR 0.08; 95% CI 0.02-0.24; p = 0.001). During the follow-up period (450 days) there was no difference in cardiovascular mortality rate [IVL (n = 5) 2.8% vs. MB (n = 3) 1.7%; p = 0.129]. Patients with unstable angina at the time of the index procedure had the highest probability of cardiovascular death [hazard ratio (HR) 7.136; 95% CI 1.248-40.802; p = 0.027]. No differences were found in long-term rates of AMI (IVL 1.7% vs. MB 2.8%; p = 0.399; IVL HR 2.73; 95% CI 0.4-17.0; p = 0.281) or TVR (IVL 5.6% vs. MB 9%; p = 0.186; IVL HR 0.78; 95% CI 0.277-2.166; p = 0.626).

Conclusion

IVL leads to a significantly better angiographic intervention outcome compared to MB angioplasty in our cohort. During long-term follow-up, no differences in cardiovascular mortality, rate of acute myocardial infarction, or target lesion failure/revascularization were observed.

The role of invasive and non-invasive imaging technologies and calcium modification therapies in the evaluation and management of coronary artery calcifications

The treatment of coronary artery disease (CAD) has advanced significantly in recent years due to improvements in medical therapy and percutaneous or surgical revascularization. However, a persistent obstacle in the percutaneous management of CAD is coronary artery calcification (CAC), which portends to higher rates of procedural challenges, post-intervention complications, and overall poor prognosis. With the advent of novel multimodality imaging technologies spanning from intravascular ultrasound to optical coherence tomography to coronary computed tomography angiography combined with advances in calcium debulking and modification techniques, CACs are now targets for intervention with growing success. This review will summarize the most recent developments in the diagnosis and characterization of CAC, offer a comparison of the aforementioned imaging technologies including which ones are most suitable for specific clinical presentations, and review the CAC modifying therapies currently available.

Clinical expert consensus document on rotational atherectomy from the Japanese association of cardiovascular intervention and therapeutics: update 2023

The Task Force on Rotational Atherectomy of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) proposed the expert consensus document to summarize the techniques and evidences regarding rotational atherectomy (RA) in 2020. Because the revascularization strategy to severely calcified lesions is the hottest topic in contemporary percutaneous coronary intervention (PCI), many evidences related to RA have been published since 2020. Latest advancements have been incorporated in this updated expert consensus document.

Aortic cusp perforation during rotational atherectomy: a case report

Background

Rotational atherectomy has become increasingly utilised over the past decade. Although a relatively safe procedure in appropriately trained physicians' hands, there are a number of recognised complications.

Case summary

We describe the case of a 64-year-old female who presented with chest pain and was diagnosed with non-ST-segment elevation acute coronary syndrome. A transthoracic echocardiogram (TTE) showed normal biventricular function and no valve disease. Invasive coronary angiogram was performed which revealed a severely calcified ostial right coronary artery (RCA) disease which was felt to be the culprit of the presentation. Balloon dilatation was unsuccessful, therefore, rotational atherectomy with an Amplatz left 0.75 guide and a 1.5 mm rota-burr was utilised and improved calcium burden. This was complicated by ostial dissection, treated with stenting. A TTE following the procedure revealed moderate aortic regurgitation (AR). The patient was discharged as she remained asymptomatic. An outpatient transoesophageal echocardiogram performed eight months later showed evidence of severe eccentric AR. Cardiac magnetic resonance imaging confirmed severe AR with left ventricular dilatation. Repeat angiogram 10 months after index procedure revealed in-stent restenosis, and the patient was accepted by heart multidisciplinary team for aortic valve replacement and grafting of RCA.

Discussion

As the field of rotational atherectomy continues to expand, we propose that novel complications such as reported in this case may become recognised. Finally, we stress the importance of multi-modality imaging in the investigation and timely planning of interventions in the management of these patients.

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.

Sustained Lumen Area by Paclitaxel-Coated Balloon Following Rotational Atherectomy for Napkin-Ring Left Main Trunk Ostial Lesion

Late lumen enlargement after percutaneous coronary intervention (PCI) with drug-coated balloon has contributed to good clinical results. However, late lumen enlargement with drug-coated balloon following rotational atherectomy has not been well reported. This report describes a case of calcified napkin-ring ostial lesion at the left main trunk that showed a sustained lumen area after PCI with drug-coated balloon following rotational atherectomy. An 85-year-old female patient was admitted to the hospital with dyspnea. Echocardiography showed hypokinesis in the anteroseptal and inferior walls. Electrocardiograph-gated cardiac computed tomography showed a calcified ostial lesion in the left main trunk. Invasive angiography of the coronary artery showed severe stenosis in the left main trunk ostium. Percutaneous coronary intervention was performed with a drug-coated balloon after rotational atherectomy. The minimal lumen area measured by intravascular ultrasound grew mildly from 4.09 to 4.17 mm2 immediately after PCI. Follow-up angiography and intravascular ultrasound performed after 6 months showed that the minimal lumen area in the left main trunk ostium was further enlarged from 4.17 to 4.69 mm2. The presence of sustained lumen area after PCI with drug-coated balloon following rotational atherectomy for a napkin-ring left main trunk ostial lesion was confirmed. This case demonstrates sustained lumen area after drug-coated balloon following rotational atherectomy in the left main trunk ostium, improving the patient's chest symptom. Hence, drug-coated balloon after rotational atherectomy may be an option for complex stent sites, such as the left main trunk ostium in geriatric patients and sites with highly calcified lesions.

Correlation between osteoprotegerin and coronary artery calcification in diabetic subjects: a systematic review of observational studies

Coronary artery calcification (CAC) is one of the critical cardiovascular complications that lead to elevated morbidity and mortality among patients with type 2 diabetes (T2M). The association between osteoprotegerin (OPG) and CAC could potentially provide a reasonable chance for preventive therapy in type 2 diabetic patients and benefit the rate of mortality. Since measurement of CAC score is relatively expensive and requires radiation exposure, the current systematic review aims to provide clinical evidence for evaluating the prognostic role of OPG in determining CAC risk among subjects with T2M. Web of Science, PubMed, Embase, and Scopus, were investigated until July 2022. We assessed human studies investigating the association of OPG with CAC in type 2 diabetic patients. Quality assessment was performed by Newcastle-Ottawa quality assessment scales (NOS). Out of 459 records, 7 studies remained eligible to be included. Observational studies that provided odds ratio (OR) estimates with 95% confidence intervals (CIs) for the association between OPG and the risk of CAC were analyzed by random-effects model. In order to provide a visual summary of our findings, the estimation of pooled OR from cross-sectional studies was reported as 2.86 [95% CI 1.49-5.49], which is consistent with the findings of the cohort study. Results revealed that the association between OPG and CAC was significant among diabetic patients. OPG is hypothesized to be a potential marker in predicting the presence of high coronary calcium score among subjects with T2M that could be recognized as a novel target for further pharmacological investigations.

Ten-year clinical outcomes of drug-eluting stents with different polymer coating strategies by degree of coronary calcification: a pooled analysis of the ISAR-TEST 4 and 5 randomised trials

BACKGROUND

Long-term data concerning the efficacy of different polymer-coating strategies of new-generation drug-eluting stents (DES) in patients with coronary artery calcification (CAC) are scant.

AIMS

We aimed to investigate 10-year outcomes by degree of CAC after new-generation DES implantation with different polymer-coating strategies.

METHODS

We analysed individual patient and lesion characteristics of patients randomised to treatment with polymer-free sirolimus-eluting, biodegradable-polymer sirolimus-eluting and permanent-polymer zotarolimus- or everolimus-eluting stents. Endpoints of interest at 10 years were all-cause mortality, myocardial infarction (MI), target lesion revascularisation (TLR) and definite or probable stent thrombosis (ST) according to the degree of CAC (no, mild, moderate or severe) and coating strategy (polymer-free vs biodegradable-polymer vs permanent-polymer).

RESULTS

A total of 4,953 patients with 6,924 lesions were included. No, mild, moderate or severe CAC was present in 24.5%, 41.8%, 25.8% and 8.0% of patients, respectively. At 10-year follow-up, overall event rates were high, with an incremental increase according to the degree of CAC (all-cause mortality: no 25.3%, mild 32.1%, moderate 41.7%, severe CAC 46.5%; adjusted [adj.] p=0.004; TLR: no 17.4%, mild 16.5%, moderate 19.8%, severe CAC 28.7%; adj. p=0.001; MI: no 4.9%, mild 5.9%, moderate 6.0%, severe CAC 10.5%; adj. p=0.02; and ST: no 1.3%, mild 1.4%, moderate 1.8%, severe CAC 3.6%; adj. p=0.57). In patients with moderate-severe CAC, event rates were comparable, regardless of the DES polymer-coating strategy.

CONCLUSIONS

At 10 years after PCI with new-generation DES, there was an incremental increase in adverse events by degree of coronary calcification. These detrimental effects do not seem to be impacted by different polymer-coating strategies.

Calcium Fracture After Intravascular Lithotripsy as Assessed With Optical Coherence Tomography

BACKGROUND

Plaque characteristics associated with effective intravascular lithotripsy (IVL) treatment of calcification have not been investigated. This study identified calcified plaque characteristics that favor the use of IVL.Methods and Results: Optical coherence tomography (OCT) was performed in 16 calcified lesions in 16 patients treated with IVL and coronary stenting. Cross-sectional OCT images in 262 segments matched across pre-IVL, post-IVL, and post-stenting time points were analyzed. After IVL, 66 (25%) segments had calcium fracture. In multivariable analysis, calcium arc (odds ratio [OR] 1.22; 95% confidence interval [CI] 1.13-1.32; P<0.0001), superficial calcification (OR 6.98; 95% CI 0.07-55.57; P=0.0182), minimum calcium thickness (OR 0.66; 95% CI 0.51-0.86; P=0.0013), and nodular calcification (OR 0.24; 95% CI 0.08-0.70; P=0.0056) were associated with calcium fracture. After stenting, stent area was larger for segments with fracture (8.0 [6.9-10.6] vs. 7.1 [5.2-8.9] mm²; P=0.004).

CONCLUSIONS

Post-IVL calcium fracture is more likely in calcified lesions with lower thickness, a larger calcium arc, superficial calcification, and non-nodular calcification, leading to a larger stent area.

Early experience with coronary debulking devices in a newcomer facility after introducing revised facility criteria in Japan

Coronary debulking devices are essential in obtaining optimal results in percutaneous coronary intervention (PCI) for severely calcified lesions. However, since the introduction of these devices in Japan, the presence of full-time cardiovascular surgeons in their own facilities has been an essential condition (on-site surgical back-up) as the facility criteria for their use. The criteria were revised in April 2020, making their implementation possible at our hospital. Between May 2020 and January 2022, we administered PCIs using rotational atherectomy (RA) for 33 lesions in 28 patients and orbital atherectomy system (OAS) for 36 lesions in 27 patients. The most preferred strategy in our hospital is OAS via the distal radial approach using a 6Fr Glide sheath or RA via the femoral approach using a 7Fr sheath. The percentages of usable imaging modality as an initial device without lesion modification were 57.1 and 66.7% in the RA and OAS groups, respectively. In the RA procedure, 1.5- and 2.0-mm Rota burrs were more frequently adopted for the initial and second sessions, respectively. In the OAS procedure, the debulking was always initiated at a low speed. Nineteen of the 27 patients underwent additional high-speed debulking. Pre-procedural quantitative coronary angiographic analysis revealed that the minimal lumen diameter was significantly smaller in the RA than in the OAS group. Debulking procedures were successful in all patients excluding two instances of procedure-related complications in the RA group, one of which was coronary perforation safely treated via covered stent deployment without any resulting hemodynamic instability. Our early experience with coronary debulking devices with off-site surgical back-up clearly reveals the safety and feasibility of this procedure in a newcomer facility.

Novel application of intravascular lithotripsy in stent under-expansion: A single-center experience

INTRODUCTION

Stent under-expansion due to calcification is associated with a less durable result. The development of intravascular lithotripsy (IVL) has provided clinicians with a readily available, simple-to-use treatment option for coronary calcification, but the use of IVL within a previously stented segment is currently off-license. There are, however, developing data suggesting that the use of IVL can be an effective treatment option for patients with calcific stent under-expansion.

METHOD

This was a single-center study of all patients treated with IVL for calcific stent under-expansion between January 2019 and June 2021. The impact of IVL on quantitative coronary angiography (QCA) stenosis and on the minimal stent area (MSA) derived from intracoronary imaging were recorded. The presence of periprocedural complications and adverse cardiovascular events was obtained from the clinical record during the study timeframe.

RESULTS

Thirty-nine patients underwent IVL for calcific stent under-expansion during the study time frame with one patient treated with more than one lesion in the same session. In all lesions, there was an improvement in the QCA stenosis with 37 (92.5%) having a residual stenosis of ≤30%. The mean QCA stenosis pre-IVL was 68 ± 21% and following IVL the mean QCA was 18 ± 9% (p < 0.001). In all lesions, there was an improvement in the MSA, with 26 (92.9%) achieving an MSA of more than 4.5 mm2 . The mean MSA pre-IVL was 3.88 ± 1.51 mm2 and following IVL the mean MSA was 7.41 ± 2.34 mm2 (p < 0.001). There were no major procedural complications. Over a mean follow-up of 506 ± 277 days, one patient died from ventricular arrhythmia but there were no other major adverse cardiovascular events.

CONCLUSION

This single-center study demonstrates that IVL is a safe and effective treatment for calcific stent under-expansion with good medium-term results.

Multimodal effects of asymmetric coating of coronary stents by electrospinning and electrophoretic deposition

Drug-eluting stents (DESs) are drug-coated vascular implants that inhibit smooth muscle cell proliferation and limit in-stent re-stenosis. However, traditional DESs release a single drug into the blood and cannot cope with complex mechanisms in atherosclerosis and body responses. The present study aimed to develop a novel multimodal stent by fabricating asymmetric coating with electrophoretic deposition and electrospinning. Herein, we use heparin-loaded alginate (Hep/Alg) and atorvastatin calcium-loaded polyurethane (AtvCa/PU) coatings on the stent luminal and abluminal surfaces, respectively. Scanning electron microscopy (SEM) micrographs showed that the alginate coatings had uniformity and thin thickness. Meanwhile, the PU fibers were formed without beads, with an acceptable diameter and suitable mechanical properties. PU nanofiber revealed minimal degradation in a 1-month study. The release of AtvCa and Hep continued for 8 days without a significant initial burst release. None of the stent coatings were cytotoxic or hemolytic, and PU nanofibers supported the survival of human umbilical endothelial cells (HUVEC) with high adhesion and flattened morphologies. The results indicate that electrophoretic deposition and electrospinning have significant potential for achieving asymmetric coating on stents and a promising approach for dual drug release for multimodal effects in vascular stent applications.

Clinical Outcomes of Biodegradable versus Durable Polymer Drug Eluting Stents in Rotational Atherectomy: Results from ROCK Registry

Background: The aim of this study was to compare the clinical outcomes of biodegradable polymer (BP) versus durable polymer (DP) drug eluting stents (DES) in patients with calcified coronary lesions who underwent rotational atherectomy (RA) and percutaneous coronary intervention (PCI). Methods: This study was based on a multicenter registry which enrolled patients with calcified coronary artery disease who received PCI using RA during between January 2010 and October 2019 from 9 tertiary centers in Korea. The primary outcome was 3-year all-cause mortality, and the secondary outcomes were cardiovascular death and target-lesion failure. Results: A total of 540 patients who underwent PCI using RA were enrolled with a follow-up period of median 16.1 months. From this registry, 272 patients with PCI using DP-DES and 238 patients with BP-SGDES were selected for analysis. PCI with BP-DES was associated with decreased all-cause mortality after propensity score matching (HR 0.414, CI 0.174–0.988) and multivariate Cox regression analysis (HR 0.458, HR 0.224–0.940). BP-DES was also associated with decreased cardiovascular mortality, but there was no difference in TLF between the two groups. Conclusions: BP-DES were associated with favorable outcomes compared to DP-DES in patients undergoing PCI using RA for calcified coronary lesions.

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.

Rotational Atherectomy or Balloon-Based Techniques to Prepare Severely Calcified Coronary Lesions

BACKGROUND

The comparative efficacy of percutaneous techniques for the preparation of calcified lesions before stenting remains poorly studied.

OBJECTIVES

This study sought to compare the performance of up-front rotational atherectomy (RA) or balloon-based techniques before drug-eluting stent implantation in severely calcified coronary lesions as assessed by angiography and optical coherence tomography (OCT).

METHODS

Patient-level data from the PREPARE-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) and ISAR-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) randomized trials were pooled. The primary endpoint was stent expansion as assessed by OCT imaging. The secondary endpoints included stent eccentricity, stent asymmetry, angiographic acute lumen gain, strategy success and in-hospital occurrence of cardiac death, target vessel myocardial infarction, and repeat revascularization.

RESULTS

Among 274 patients originally randomized, 200 participants with available OCT data after lesion preparation with RA (n = 63), a modified balloon (MB, n = 103), or a super high-pressure balloon (n = 34) before stenting were analyzed. The use of RA versus MB or a super high-pressure balloon led to comparable stent expansion (73.2% ± 11.6% vs 70.8% ± 13.6% vs 71.8% ± 12.2%, P = 0.49) and stent asymmetry (P = 0.83). Compared with RA or MB, a super high-pressure balloon was associated with less stent eccentricity (P = 0.03) with a numerically higher acute lumen gain, albeit not significantly different (P = 0.08). Strategy success was more frequent with RA versus MB (P = 0.002) and numerically more frequent with RA versus a super high-pressure balloon (P = 0.06). Clinical outcomes did not differ between groups.

CONCLUSIONS

In patients with severely calcified lesions undergoing drug-eluting stent implantation, lesion preparation with RA, MB, or a super high-pressure balloon was associated with comparable stent expansion. A super high-pressure balloon is associated with less stent eccentricity, whereas strategy success is more frequent with RA.

Drug-Eluting, Bioresorbable Cardiovascular Stents─Challenges and Perspectives

Globally, the leading causes of natural death are attributed to coronary heart disease and type 1 and type 2 diabetes. High blood pressure levels, high cholesterol levels, smoking, and poor eating habits lead to the agglomeration of plaque in the arteries, reducing the blood flow. The implantation of devices used to unclog vessels, known as stents, sometimes results in a lack of irrigation due to the excessive proliferation of endothelial tissue within the blood vessels and is known as restenosis. The use of drug-eluting stents (DESs) to deliver antiproliferative drugs has led to the development of different encapsulation techniques. However, due to the potency of the drugs used in the initial stent designs, a chronic inflammatory reaction of the arterial wall known as thrombosis can cause a myocardial infarction (MI). One of the most promising drugs to reduce this risk is everolimus, which can be encapsulated in lipid systems for controlled release directly into the artery. This review aims to discuss the current status of stent design, fabrication, and functionalization. Variables such as the mechanical properties, metals and their alloys, drug encapsulation and controlled elution, and stent degradation are also addressed. Additionally, this review covers the use of polymeric surface coatings on stents and the recent advances in layer-by-layer coating and drug delivery. The advances in nanoencapsulation techniques such as liposomes and micro- and nanoemulsions and their functionalization in bioresorbable, drug-eluting stents are also highlighted.

Percutaneous coronary intervention in calcified stenoses: a protocol for a systematic review with meta-analysis, trial sequential analysis and network meta-analysis

INTRODUCTION

Severely calcified coronary stenoses are difficult to treat with percutaneous coronary interventions. The presence of severe calcifications complicates lesion preparation, advancement of stents and achievement of full stent expansion. Intervention in these lesions is associated with an increased risk of complications and procedural failure compared with treatment of less calcified lesions. Due to the high burden of comorbidity, patients with severely calcified lesions are often excluded from interventional trials, and there is little evidence on how to treat these patients.

METHODS AND ANALYSIS

We will conduct a systematic review of randomised trials enrolling patients with calcified coronary artery disease undergoing percutaneous coronary intervention. We will investigate any percutaneous treatment option including any lesion preparation, stenting or postdilatation technique. We will search The Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval System Online, Latin American and Caribbean Health Sciences Literature, Science Citation Index Expanded, and Excerpta Medica database for studies from inception to 31 October 2022. The coprimary outcome is all-cause mortality and serious adverse events. If appropriate, we will conduct meta-analysis, trial sequential analysis and network meta-analysis.

ETHICS AND DISSEMINATION

No ethics approval is required for this study. The results will be published in a peer-reviewed journal in this field.

PROSPERO REGISTRATION NUMBER

CRD42021226034.

Clinical Outcomes of Different Calcified Culprit Plaques in Patients with Acute Coronary Syndrome

Background: Previous studies have found that coronary artery calcification is closely associated with the occurrence of major adverse cardiac events (MACE). This study aimed to investigate the characteristics and clinical outcomes of different calcified plaques in patients with acute coronary syndrome (ACS) by using optical coherence tomography (OCT). Methods: 258 ACS patients with calcified culprit plaques who underwent OCT-guided stent implantation were enrolled. They were divided into three subtypes based on the calcified plaque morphology, including eruptive calcified nodules, calcified protrusion, and superficial calcific sheet. Results: Compared with superficial calcific sheet and calcified protrusion, eruptive calcified nodules had the greatest calcium burden and a higher rate of stent edge dissection (p < 0.001) and incomplete stent apposition (p < 0.001). In a median follow-up period of 2 years, 39 (15.1%) patients experienced MACE (a composite event of cardiac death, target-vessel myocardial infarction, ischemia-driven revascularization), with a significantly higher incidence in the eruptive calcified nodules group (32.1% vs. 10.1% vs. 13.0%, p = 0.001). A multivariate Cox analysis demonstrated that the eruptive calcified nodules (hazard ratio 3.14; 95% confidence interval, 1.64−6.02; p = 0.001) were an independent predictor of MACE. Conclusions: MACE occurred more frequently in ACS patients with eruptive calcified nodules, and the eruptive calcified nodules were an independent predictor of MACE.

High-definition intravascular ultrasound versus optical frequency domain imaging for the detection of calcium modification and fracture in heavily calcified coronary lesion

While optical frequency domain imaging (OFDI) can delineate calcium modification and fracture, the capability of high-definition intravascular ultrasound (HD-IVUS) for detecting these remains unclear. This study evaluated diagnostic accuracy of HD-IVUS for assessing calcium modification and fracture as compared to OFDI. HD-IVUS and OFDI were used during orbital or rotational atherectomy procedures conducted for 21 heavily calcified coronary lesions in 19 patients. With OFDI assessment used as the gold standard, diagnostic accuracies of HD-IVUS for calcium modification and fracture were compared every 1 mm to the matched pre-stenting images (n = 1129). Calcium modification, as assessed by OFDI, was defined as polished and concave-shaped calcium. For HD-IVUS, calcium modification was defined as the presence of reverberation with concave-shaped calcium. In both assessments, the definition of calcium fracture was defined as a slit or complete break in the calcium plate. Calcified plaque was found in 86.4% of analyzed OFDI images. Calcium modification and fracture were detected in 20.6% and 11.0% of detected calcified plaques. Sensitivity, specificity, positive and negative predictive values of HD-IVUS detection for calcium modification and fracture were 54.4%, 97.8%, 86.7%, 89.1% and 86.0%, 94.5%, 58.2%, 96.8%, respectively. Discordance cases between both assessments demonstrated that heterogeneous calcium visualized by OFDI, separated calcium, and guide wire artifact can be misdiagnosed. Diagnostic accuracies of HD-IVUS for assessing calcium modification and fracture were acceptable as compared to OFDI. Such findings can be of utility during imaging guided interventional procedures with atherectomy.

Effect of Atherectomy on Lesion Preparation in Heavily Calcified Coronary Artery Disease

Background: Percutaneous coronary intervention (PCI) of heavily calcified lesions remains challenging. This study examined whether calcified lesion preparation is better with an ablation-based than balloon-based technique. Methods and Results: Results of lesion preparations with and without atherectomy devices were compared in 121 patients undergoing optical coherence tomography (OCT)-guided PCI of heavily calcified lesions. Lesion preparation was performed with the ablation-based technique in 59 patients (atherectomy group) and with the balloon-based technique in 62 patients (balloon group). Lower grades of angiographic coronary dissections (National Heart, Lung, and Blood Institute [NHLBI] classification) occurred in the atherectomy than balloon group (atherectomy group: none, 33%; NHLBI A, 59%; B, 8%; C, 0%; D, 0%; balloon group: none, 1%; NHLBI A, 24%; B, 58%; C, 15%; D, 2%). On OCT, a large dissection was less common (49% vs. 90%; P<0.001) and calcium fractures were more frequent (75% vs. 18%; P<0.001) in the atherectomy than balloon group. In multivariable analyses, the ablation-based technique was associated with a lower grade of angiographic coronary dissection (adjusted odds ratio [aOR] 0.04; 95% confidence interval [CI] 0.01-0.12; P<0.001), a lower incidence of OCT-detected large dissection (aOR 0.09; 95% CI 0.03-0.30; P<0.001), and a higher incidence of OCT-detected calcium fracture (aOR 18.19; 95% CI 6.45-58.96; P<0.001). Conclusions: The ablation-based technique outperformed the balloon-based technique in the lesion preparation of heavily calcified lesions.