Intravascular lithotripsy for severe coronary calcification: a systematic review

INTRODUCTION

Coronary artery calcification remains a challenge in percutaneous coronary interventions, due to the higher risk of suboptimal result with subsequent poor clinical outcomes. Intravascular lithotripsy is a novel way of treating severe coronary calcification as it has the ability to modify calcium both circumferentially as well as transmurally, facilitating stent expansion and apposition. We conducted a systematic overview of the published literature on intravascular lithotripsy (IVL) assessing the efficacy and feasibility of IVL in treating severe coronary calcification.

EVIDENCE ACQUISITION

Of the retrieved publications, 62 met our inclusion criteria and were included. A total of 1389 patients (1414 lesions) with significant coronary calcification or under-expanded stents underwent IVL.

EVIDENCE SYNTHESIS

The mean age was 72.03 years (74.7% male). There was a significant improvement in acute and sustained vessel patency, with mean minimal lumen diameter of 2.78±0.46 mm, resulting in acute gain of 1.72±0.51 mm. The acute procedural success rate was 78.2 to 100% with in-hospital complication rate of 5.6 to 7.0%. The majority of the studies reported 30-day MACE, which was between 2.2 to 7.8%.

CONCLUSIONS

The recent studies have highlighted that the use of IVL with adjuvant intracoronary imaging has revolutionized the way of treating heavily calcified, non-dilatable coronary lesions and is likely to succeed the conventional ways of treating these complex lesions. We need further studies to gauge the long-term efficacy and safety of IVL against techniques currently available for calcium modification including conventional balloons, cutting or scoring balloons, rotational atherectomy and laser atherectomy.

Positive remodelling of coronary arteries on computed tomography coronary angiogram: an observational study

BACKGROUND

Coronary artery disease (CAD) due to atherosclerosis is projected to be the leading cause of morbidity and mortality worldwide until 2040. CAD affects approximately 2.6 million people in the United Kingdom (UK), and 1 in 4 of them do not experience any symptoms.

AIMS

The aim of this study was to assess the characteristics and outcomes of patients with plaque features of positive remodelling (PR) on their computed tomography coronary angiogram (CTCA) images.

METHODS

Patients who were referred for CTCA from June 2018 to January 2020 were retrospectively identified. Patients underwent prospective, gated 128-slice dual-source CTCA. Patients with PR were compared to those without PR for demographics and outcomes.

RESULTS

A total of 861 patients were included in our study; 241 (28%) had PR, and 620 (72%) had no PR. Patients with PR were older (PR: 63.9±11.0 years vs no PR: 62.1±11.2 years; p=0.04), more likely to be male (PR: 65.6% vs no PR: 55.8%; p=0.01) and underwent coronary angiography more frequently (PR: 25.7% vs no PR: 14.4%; p<0.01). There were also significant increases in subsequent acute coronary syndrome (ACS) events (PR: 2.5% vs no PR: 0.0%; p<0.01) and the need for revascularisation therapy (PR: 15.4% vs no PR: 7.8%; p<0.01) in patients with PR despite being on statins (not a high dose). There was no difference in all-cause mortality.

CONCLUSIONS

Detection of PR on CTCA is a reliable prognostic indicator of future cardiovascular events and presents a valuable opportunity for initiation of aggressive primary prevention therapy.

ECG changes in hospitalised patients with COVID-19 infection

The coronavirus disease 2019 (COVID-19) commonly involves the respiratory system but increasingly cardiovascular involvement is recognised. We assessed electrocardiogram (ECG) abnormalities in patients with COVID-19. We performed retrospective analysis of the hospital's COVID-19 database from April to May 2020. Any ECG abnormality was defined as: 1) new sinus bradycardia; 2) new/worsening bundle-branch block; 3) new/worsening heart block; 4) new ventricular or atrial bigeminy/trigeminy; 5) new-onset atrial fibrillation (AF)/atrial flutter or ventricular tachycardia (VT); and 6) new-onset ischaemic changes. Patients with and without any ECG change were compared. There were 455 patients included of whom 59 patients (12.8%) met criteria for any ECG abnormality. Patients were older (any ECG abnormality 77.8 ± 12 years vs. no ECG abnormality 67.4 ± 18.2 years, p<0.001) and more likely to die in-hospital (any ECG abnormality 44.1% vs. no ECG abnormality 27.8%, p=0.011). Coxproportional hazard analysis demonstrated any ECG abnormality (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.12 to 3.47, p=0.019), age (HR 1.03, 95%CI 1.01 to 1.05, p=0.0009), raised high sensitivity troponin I (HR 2.22, 95%CI 1.27 to 3.90, p=0.006) and low estimated glomerular filtration rate (eGFR) (HR 1.73, 95%CI 1.04 to 2.88, p=0.036) were independent predictors of in-hospital mortality. In conclusion, any new ECG abnormality is a significant predictor of in-hospital mortality.

Rotablation in the Very Elderly - Safer than We Think?

BACKGROUND/PURPOSE

Calcified coronary artery stenosis remains a challenge for Percutaneous Coronary Intervention (PCI). Calcium modification is facilitated by rotablation and is used in 1-3% of cases. Data on rotablation in patients ≥80 years is limited and perceived to be high risk. We compared PCI with rotablation and outcomes between patients ≥80 years and those <80 years.

METHODS/MATERIALS

Retrospective analysis was performed of consecutive patients who underwent rotablation and PCI from 3 United Kingdom (UK) PCI Centres (2014-2017). In-hospital outcomes (composite of stroke, myocardial infarction, death, emergency coronary artery bypass graft surgery, vascular damage, coronary perforation, advanced AV-block, bleeding and renal impairment) and 30 day mortality risk score was compared between groups.

RESULTS

213 patients were included. 33.3% (n = 71) were ≥80 years. Baseline and angiographic characteristics were similar in the two groups. Older patients were more likely to present with acute coronary syndrome (ACS) (≥80 years 53.5% vs. 33.8% in <80 years, p = 0.006) and had increased hospital stay (≥80 years 2.8 days (±6.0) vs. 1.3 days (±1.9) <80 years, p = 0.009). Majority of PCI were performed through radial access (≥80 years 91.5% vs. 88.0% <80 years, p = 0.43). In-hospital composite outcomes were similar between the groups (≥80 years 5.6% vs. 4.9% <80 years, p = 1.0). The 30-day mortality risk score demonstrated a higher average risk of 2.5% in ≥80 years versus under 1% risk in <80 years (p < 0.001).

CONCLUSION

This study demonstrates that outcomes after rotablation in the very elderly are similar to younger patients despite being high risk and presenting with ACS.

A detailed analysis of patients included in the Summary Hospital-level Mortality Indicator (SHMI) for myocardial infarction (MI)-all is not what it seems?

Background

The Summary Hospital-level Mortality Indicator (SHMI) for Myocardial Infarction (MI) is the ratio of the observed to the expected number of deaths due to MI. We aimed to assess (1) the accuracy of MI as a diagnosis in the SHMI for MI and (2) the healthcare received by patients with type 1 MI included in the SHMI for MI.

Methods

Retrospective review of patients included in SHMI for MI from April 2017 to March 2018. The diagnosis of MI was divided into type 1, type 2 and non-MI. For patients with type 1 MI who underwent intervention, we applied the prognostic Toronto Risk Score (TRS) and classified into group 0: score <13 (mortality risk 0%–4%, lowest risk), group 1: score 13–16 (mortality risk 6%–19.6%), group 2: score 17–19 (mortality risk 27.4%–47.6%) and group 3: score ≥20 (mortality risk 58%–92%). For patients with type 1 MI who underwent conservative management, we reviewed appropriateness of conservative management.

Results

SHMI for MI was 96 (41/42.83) falling to 65.4 with the inclusion of only type 1 MI (28 patients, 28/42.83). About 41.5% (n=17) underwent intervention of whom three were in the lowest risk TRS (group 0) and all received appropriate healthcare. Conservative management was appropriate for the 26.8% (n=11) treated medically, the most common reason was severe cognitive dysfunction.

Conclusions

We have demonstrated that SHMI for MI can be inaccurate due to the inclusion of type 2 MI or non-MI. Grouping patients into intervention versus conservative management helps in assessment of healthcare.

Twelve-month outcomes of patients unsuitable for prolonged DAPT presenting with an acute coronary syndrome and treated with polymer-free biolimus A9 drug-coated stents

INTRODUCTION

Prolonged dual anti-platelet therapy (DAPT) is undesirable in certain patients. The biolimus-A9 drug-coated stent (BA9-DCS) has a rapid drug-elution profile allowing shortened DAPT.

METHODS

The demographics, procedural data, and clinical outcomes for 505 patients presenting with an ACS to three UK centres and treated with a BA9-DCS stent (PCI-DCS) were collected, and compared to a consecutive ACS cohort of unselected patients treated in the same period with drug-eluting stents (PCI-DES).

RESULTS

PCI-DCS patients were older, more often female with hypertension, chronic kidney disease, severe LV dysfunction, and peripheral vascular disease more frequent than the PCI-DES cohort. PCI-DCS patients had a much higher Mehran bleed risk score (21.5 ± 7.7 vs. 15.9 ± 7.7, P < 0.0001). Baseline disease burden was greater in the PCI-DCS cohort with more left main and three vessel disease. During PCI, more stents (1.91 ± 1.1 vs. 1.57 ± 0.94, P < 0.0001), total stent length (38.2 ± 20.8 vs. 31.4 ± 20.3, P < 0.0001) and longer stents (38.2 ± 20.8 vs. 31.4 ± 20.3 mm, P < 0.0001) were used in the PCI-DCS cohort with rotational atherectomy also used more frequently. Physician-recommended DAPT duration was 2.9 ± 3.9 months for PCI-DCS patients and 11.3 ± 2.4 months for PCI-DES patients (P < 0.0001). At 12-month follow-up, definite stent thrombosis (0.6% vs. 1.1%) and TLR (3.2% vs. 2.7%) rates were similar between the two groups. After adjustment for baseline differences, there were no statistically significant differences in death and combined MACE rates at 12 months.

CONCLUSIONS

The outcomes of patients treated with polymer-free BA9 drug-coated stent who present with an ACS and who were deemed unsuitable for prolonged DAPT are encouraging. Further studies are warranted.

Dietary Nitrate Supplementation Reduces Circulating Platelet-Derived Extracellular Vesicles in Coronary Artery Disease Patients on Clopidogrel Therapy: A Randomised, Double-Blind, Placebo-Controlled Study

Extracellular vesicles (EVs) are implicated in the pathogenesis of cardiovascular disease (CVD). Specifically, platelet-derived EVs are highly pro-coagulant, promoting thrombin generation and fibrin clot formation. Nitrate supplementation exerts beneficial effects in CVD, via an increase in nitric oxide (NO) bioavailability. Clopidogrel is capable of producing NO-donating compounds, such as S-nitrosothiols (RSNO) in the presence of nitrite and low pH. The aim of this study was to assess the effect of nitrate supplementation with versus without clopidogrel therapy on circulating EVs in coronary artery disease (CAD) patients. In this randomized, double-blind, placebo-controlled study, CAD patients with (n = 10) or without (n = 10) clopidogrel therapy received a dietary nitrate supplement (SiS nitrate gel) or identical placebo. NO metabolites and platelet activation were measured using ozone-based chemiluminescence and multiple electrode aggregometry. EV concentration and origin were determined using nanoparticle tracking analysis and time-resolved fluorescence. Following nitrate supplementation, plasma RSNO was elevated (4.7 ± 0.8 vs 0.2 ± 0.5 nM) and thrombin-receptor mediated platelet aggregation was reduced (-19.9 ± 6.0 vs 4.0 ± 6.4 U) only in the clopidogrel group compared with placebo. Circulating EVs were significantly reduced in this group (-1.183e¹¹ ± 3.15e¹⁰ vs -9.93e⁹± 1.84e¹⁰ EVs/mL), specifically the proportion of CD41+ EVs (-2,120 ± 728 vs 235 ± 436 RFU [relative fluorescence unit]) compared with placebo. In vitro experiments demonstrated clopidogrel-SNO can reduce platelet-EV directly (6.209e¹⁰± 4.074e⁹ vs 3.94e¹¹ ±  1.91e¹⁰ EVs/mL). In conclusion, nitrate supplementation reduces platelet-derived EVs in CAD patients on clopidogrel therapy, increasing patient responsiveness to clopidogrel. Nitrate supplementation may represent a novel approach to moderating the risk of thrombus formation in CAD patients.

Comparison of the Effects of Incomplete Revascularization on 12-Month Mortality in Patients <80 Compared With ≥80 Years Who Underwent Percutaneous Coronary Intervention

Although randomized trial data suggest that complete revascularization improves outcomes after percutaneous coronary intervention (PCI), the impact of differing revascularization strategies in octogenarians is not well defined. We performed a retrospective analysis, which was conducted of 9,628 consecutive patients who underwent PCI at a large UK center. Octogenarians were more likely to have significant co-morbidity, a higher Mehran bleed risk score (24.5 ± 6.8 vs 13.3 ± 7.4, p <0.0001), and more complex disease (baseline SYNTAX score 18.7 ± 11.0 vs 13.1 ± 8.9, p = 0.002) than younger patients. During PCI, octogenarians were more likely to undergo left main or proximal LAD intervention, but despite this, significantly less likely to receive drug-eluting stents (66.5% vs 80.1%, p <0.001). Postprocedurally, octogenarians had greater residual disease burden (residual SYNTAX score 10.1 ± 8.7 vs 1.6 ± 3.3, p <0.0001). At 12 months, adverse outcomes (definite stent thrombosis 3.3% vs 1.1%, p <0.001, clinically driven in-stent restenosis PCI 3.7% vs 2.6%, p = 0.005, and 12-month mortality 12.8% vs 4.2%, p <0.0001) were all more frequent in octogenarians. Although age, shock, diabetes, and BMS use were independently predictive of increased 12-month mortality, incomplete revascularization was not. In conclusion, octogenarians are a complex group to treat balancing high-risk bleeding profile and complex coronary disease. However, in multivariate analysis, incomplete revascularization was not independently predictive of adverse outcomes. These data support a conservative target lesion-only DES-driven revascularization strategy.

Early Clinical Experience with a Polymer-Free Biolimus A9 Drug-Coated Stent in DES-Type Patients Who Are Poor Candidates for Prolonged Dual Anti-Platelet Therapy

Introduction

Prolonged dual anti-platelet therapy (DAPT) may cause excess bleeding in certain patients. The biolimus-A9 drug-coated stent (BA9-DCS) has a rapid drug-elution profile allowing shortened DAPT. Data were gathered on the early experience implanting this stent in drug-eluting stent eligible patients deemed to be at high risk of bleeding.

Background and Methods

The demographics, procedural data and clinical outcomes were gathered prospectively for 249 patients treated with a BA9-DCS stent at 2 UK centres, and compared to a cohort of patients treated in the same period with drug-eluting stents (PCI-DES).

Results

Operator-defined BA9-DCS indications included warfarin therapy, age, and anaemia. Patients receiving a BA9-DCS were older (71.6±11.8 vs. 64.8±11.6yrs, p<0.001), more often female (38.2 vs. 26.8%, P<0.001), and more likely to have comorbidity including chronic kidney disease or poor LV function than PCI-DES patients. The baseline Mehran bleed risk score was also significantly higher in the BA9-DCS group (19.4±8.7 vs. 13.1±5.8, p<0.001). Of the BA9-DCS cohort, 95.5% of patients demonstrated disease fitting NICE criteria for DES placement. The number of lesions treated (1.81±1.1 vs. 1.58±0.92, p = 0.003), total lesion length (32.1±21.7 vs. 26.1±17.6mm, p<0.001), number of stents used (1.93±1.11 vs. 1.65±1.4, p = 0.007) and total stent length (37.5±20.8 vs. 32.4±20.3, p<0.01) were greater for BA9-DCS patients. DAPT was prescribed for 3.3±3.9 months for BA9-DCS patients and 11.3±2.4 months for PCI-DES patients (p<0.001). At follow up of 392±124 days despite the abbreviated DAPT course stent related event were infrequent with ischemia-driven restenosis PCI (2.8 vs. 3.4%, p = 0.838), and stent thrombosis (1.6 vs. 2.1%, p = 0.265) rates similar between the BA9-DCS ad PCI-DES groups. After propensity scoring all clinical end-points were similar between both cohorts.

Conclusions

This early experience using polymer-free BA9 drug-coated stents in drug-eluting stent type patients at risk of bleeding are encouraging. Further studies are warranted.