Initial and Long-Term Outcomes of Sirolimus-Eluting Stents for Calcified Lesions Compared With Bare-Metal Stents

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.

Chronic stent recoil in severely calcified coronary artery lesions. A serial optical coherence tomography study

Chronic second-generation drug-eluting stent recoil in severely calcified coronary lesions has not been studied. We aimed to evaluate chronic stent recoil by optical coherence tomography (OCT) in severely calcified lesions treated with thin strut stents after rotational atherectomy. In 28 lesions (26 patients with 23% on hemodialysis) treated with everolimus-eluting stents after rotational atherectomy, baseline and 8-month follow-up OCT were compared. Stent recoil was defined as >10% decrease in stent area from baseline to follow-up. Overall, there was no change in minimal stent area (6.0 mm² [5.0, 8.1] to 6.0 mm² [4.8, 8.6], p = 0.51) from baseline to follow-up, although neointimal hyperplasia measured 16.3 ± 15.8%. Thirty-six percent of lesions showed stent recoil associated with 6 non-nodular calcifications, 1 calcified nodule, and 3 stent deformations. The overall mean calcium angle with attenuation decreased (54° [29-76] to 31° [19-48], p < 0.0001), and calcium without attenuation increased (28° [21-67] to 64° [34-93], p < 0.0001), but primarily at the location of stent recoil. Furthermore, in the stent recoil segments in 10 recoil lesions, the stent circumference decreased primarily at non-calcium segments rather than at calcium with or without attenuation. One lesion with stent recoil and 2 lesions without stent recoil required repeat revascularization. Thin strut stents can chronically recoil in severely calcified lesions, but this rarely causes restenosis.

One-Year Outcomes After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction With Varying Quantities of Coronary Artery Calcium (from a 13-Year Registry)

Coronary artery calcium (CAC) is associated with poor angiographic results and higher rates of complications after percutaneous coronary intervention (PCI). Limited data are available regarding the impact of angiographically evident CAC on long-term outcomes after primary PCI in patients presenting with ST-segment elevation myocardial infarction (STEMI). In this single-center, registry-based retrospective cohort analysis, we analyzed 2,143 consecutive patients presenting with STEMI who underwent primary PCI within 12 hours of symptom onset. Patients were divided based on degree of CAC (determined by visual inspection of angiograms) as follows: (1) moderate-to-severe CAC (n = 306; 14.3%) and (2) minimal-to-none CAC (n = 1,837; 85.7%). The primary end point was all-cause mortality at 1-year after PCI. Patients with moderate-to-severe CAC were older, women, and had higher rates of hypertension, chronic kidney disease, and peripheral vascular disease. Moderate-to-severe CAC was associated with higher rates of anterior myocardial infarction, advanced Killip class, and poor final angiographic results. At 1-year follow-up, rates of all-cause mortality were higher in the moderate-to-severe CAC cohort than those in the minimal-to-none CAC cohort (8.5% vs 4.7%; p = 0.008). However, after accounting for major clinical and angiographic characteristics, moderate-to-severe CAC on presenting STEMI angiogram was no longer predictive of 1-year all-cause mortality. In conclusion, advanced CAC burden occurs in ∼15% of patients undergoing primary PCI for STEMI and reflects a marker of adverse prognosis late into follow-up after PCI.

Clinical outcome of drug-eluting versus bare-metal stents in patients with calcified coronary lesions: a meta-analysis

BACKGROUND

The relative safety and efficacy of drug-eluting stents (DES) versus bare-metal stents (BMS) in patients with calcified coronary lesions is still debated.

AIMS

To evaluate clinical outcome of DES versus BMS in patients with calcified coronary lesions using a meta-analysis of the current literature.

METHODS

We performed a systematic literature search using Medline, Embase, Cochrane and several other databases. Randomised controlled trials, prospective and retrospective cohort studies with a mean follow-up period >6 months were included. Primary efficacy was target lesions revascularisation (TLR) and primary end-point for safety was stent thrombosis. Secondary end-points were cardiac death and recurrent myocardial infarction (MI).

RESULTS

Five trials were included in the meta-analysis, including 2440 patients (1230 in the DES group, 1210 in the BMS group). TLR was significantly lower in patients treated with DES as compared with patients treated with BMS (8.5% vs 16.0%; odds ratio (OR) = 0.50; 95% confidence interval (CI) 0.38-0.65; P < 0.00001). There were no significant differences in the incidence of stent thrombosis (0.9% vs 0.3%; OR = 2.01; 95% CI 0.34-11.88; P = 0.44), cardiac death (3.3% vs 4.2%; OR = 0.81; 95% CI 0.50-1.30; P = 0.38) and recurrent MI (5.0% vs 5.2%; OR = 0.99; 95% CI, 0.66-1.49; P = 0.97) between the two groups. Subgroup analysis by the sample size and follow-up duration showed that the associations were similar between DES versus BMS.

CONCLUSIONS

DES significantly reduces TLR rates as compared with BMS in patients with calcified coronary lesions, with non-significant differences in terms of stent thrombosis, cardiac death and MI.

The clinical and cost burden of coronary calcification in a Medicare cohort: An economic model to address under-reporting and misclassification

BACKGROUND

Coronary artery calcification (CAC) is a well-established risk factor for the occurrence of adverse ischemic events. However, the economic impact of the presence of CAC is unknown.

OBJECTIVES

Through an economic model analysis, we sought to estimate the incremental impact of CAC on medical care costs and patient mortality for de novo percutaneous coronary intervention (PCI) patients in the 2012 cohort of the Medicare elderly (≥65) population.

METHODS

This aggregate burden-of-illness study is incidence-based, focusing on cost and survival outcomes for an annual Medicare cohort based on the recently introduced ICD9 code for CAC. The cost analysis uses a one-year horizon, and the survival analysis considers lost life years and their economic value.

RESULTS

For calendar year 2012, an estimated 200,945 index (de novo) PCI procedures were performed in this cohort. An estimated 16,000 Medicare beneficiaries (7.9%) were projected to have had severe CAC, generating an additional cost in the first year following their PCI of $3500, on average, or $56 million in total. In terms of mortality, the model projects that an additional 397 deaths would be attributable to severe CAC in 2012, resulting in 3770 lost life years, representing an estimated loss of about $377 million, when valuing lost life years at $100,000 each.

CONCLUSIONS

These model-based CAC estimates, considering both moderate and severe CAC patients, suggest an annual burden of illness approaching $1.3 billion in this PCI cohort. The potential clinical and cost consequences of CAC warrant additional clinical and economic attention not only on PCI strategies for particular patients but also on reporting and coding to achieve better evidence-based decision-making.

Long-term safety and performance of the orbital atherectomy system for treating calcified coronary artery lesions: 5-Year follow-up in the ORBIT I trial

BACKGROUND/PURPOSE

The ORBIT I trial, a first-in-man study, was conducted to evaluate the safety and performance of the orbital atherectomy system (OAS) in treating de novo calcified coronary lesions.

METHODS/MATERIALS

Fifty patients were enrolled between May and July 2008 based on several criteria, and were treated with the OAS followed by stent placement. The safety and performance of the OAS were evaluated by procedural success, device success, and overall major adverse cardiovascular event (MACE) rates, including cardiac death, myocardial infarction (MI) and need for target lesion revascularization (TLR). Our institution enrolled and treated 33 of the 50 patients and continued follow-up for 5 years.

RESULTS

Average age was 54 years and 91% were males. Mean lesion length was 15.9 mm. Device success was 100%, and average number of orbital atherectomy devices (OAD) used per patient was 1.3. Stents were placed directly after OAS in 31/32 patients (96.9%). All stents (average stent per lesion 1.1) were successfully deployed with 0.3% residual stenosis. The overall cumulative MACE rate was 6.1% in-hospital, 9.1% at 30 days, 12.1% at 6 months, 15.2% at 2 years, 18.2% at 3 years and 21.2% at 5 years (4 total cardiac deaths). None of the patients had Q-wave MIs. Angiographic complications were observed in 5 patients. No flow/slow flow due to distal embolization was observed.

CONCLUSIONS

The ORBIT I trial suggests that OAS treatment continues to offer a safe and effective method to change compliance of calcified coronary lesions to facilitate optimal stent placement in these difficult-to-treat patients.

Percutaneous coronary intervention of moderate to severe calcified coronary lesions: insights from the National Heart, Lung, and Blood Institute Dynamic Registry

OBJECTIVES

To evaluate the efficacy and safety of drug eluting stents (DES) when compared with bare metal stents (BMS) in patients with moderate to severe calcified coronary lesions.

BACKGROUND

Calcified coronary lesions present unique technical challenges during percutaneous coronary intervention (PCI) and it is not known if DES are as safe and as effective in the presence of calcium, as randomized trials typically exclude this common patient subset.

METHODS

We evaluated patients with PCI of a single calcified lesion enrolled across five recruitment waves in the National Heart, Lung, and Blood Institute Dynamic Registry between 1997 and 2006. Patients were divided into two groups based on the stent type- BMS and DES. The primary efficacy outcome was the need for repeat revascularization at 1 year and the primary safety outcome was a composite of death and myocardial infarction at 1 year.

RESULTS

Among the 1,537 patients included in the analysis, 884 (57%) underwent PCI with BMS and 653 (43%) with DES. DES use was associated with a significant reduction in the risk of repeat revascularization (10.0% vs. 15.3%; P = 0.003) with no significant higher risk of primary safety outcome (9.3% vs. 10.5%; P = 0.45) when compared to the BMS group. In a propensity score adjusted analysis, DES use was associated with a significantly lower risk in repeat revascularization (HR = 0.57; 95% CI 0.40-0.82; P = 0.002) and no significant difference in the risk of death and myocardial infarction (HR = 0.78; 95% CI 0.53-1.15; P = 0.20) compared to BMS group.

CONCLUSION

In this large multicenter registry of patients with a moderate to severe calcified coronary lesion, use of DES compared to BMS was associated with significant reduction in the risk of repeat revascularization without any increase in death and myocardial infarction.

Off-label use of drug-eluting versus bare metal stents: a lesion-specific systematic review of long-term outcomes

OBJECTIVE

The purpose of this systematic review was to evaluate differences in lesion-specific outcomes with the "off-label" use of drug-eluting stents (DES) versus bare metal stents (BMS).

METHODS

MEDLINE, PubMed, the Cochrane databases, and other Web were searched for studies evaluating off-label use of DES and BMS with the same characteristics. Of 1,258 abstracts or manuscripts reviewed, 112 studies were included (total N = 23,438). Studies were excluded if patients received both types of stent or no stent; lesion type was unknown; lesion-specific outcomes for ≥6 months were unavailable; or <25 patients were enrolled.

RESULTS

Overall mortality at 6-12 months was approximately 3% for BMS and DES for off-label use. Increase in mortality was greater from 6-12 months to 2 years with BMS than with DES (3.3%-9.1%; 2.8%-4.1%); however, rates were similar at 3 years (BMS: 18.8%; DES:15.3%). Myocardial Infarction rates were similar for both types at 6-12 months (BMS: 6.5%; DES: 6.0%). Overall rates of stent thrombosis were 1.8% and 1.7% for BMS and DES, respectively. Similar or slightly lower rates of stent thrombosis were seen for most lesion types, except higher rates for small vessels for BMS (5.2%) and true bifurcation for DES (3.3%). Rates of target lesion revascularization (TLR) were 7.5% for BMS and 19.6% for DES at 6-12 months. At 2-years TLR remained lower than DES. When the combined group was compared to registry data alone, similar values were seen.

CONCLUSIONS

Rates of mortality, myocardial infarction (MI), and stent thrombosis were similar in patients receiving BMS or DES, while TLR rates were lower in DES patients.

Comparison of long-term outcomes following sirolimus-eluting stent vs paclitaxel-eluting stent implantation in patients with long calcified coronary lesions

BACKGROUND

Although previously reported studies on coronary calcification mainly focused on its presence or absence in discrete focal target lesions, calcified coronary lesions (CCL) angiographically present as diffuse long lesions in some patients. The aim of our study was to evaluate the long-term efficacy of sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) on long CCL.

METHODS

A total of 122 patients with 134 lesions (77 patients with 88 lesions for SES and 45 patients with 46 lesions for PES) were enrolled from 3 centers. Long CCL was defined visually as a culprit lesion with type B or C that was mainly due to coronary calcification with > 20 mm in total length by coronary angiography. Clinical follow-up was performed at 1 year and angiographic follow-up at 6 to 9 months after procedure. Major adverse coronary events (MACE) were defined as all-cause death, myocardial infarction (MI), and repeat target-lesion revascularization (TLR).

RESULTS

There were no statistically significant differences in baseline, procedural, or angiographic characteristics and in 1-year rates of all-cause death, MI, and TLR between the 2 groups (all P = NS [not significant]). Likewise, the cumulative incidence of MACE at 1 year was similar between the 2 groups (7.8% of patients in the SES group vs 4.4% of patients in the PES group, respectively, P = NS). In patients who underwent follow-up angiography, the angiographic binary restenosis rate was 6.2% in the SES group vs 12.1% in the PES group, respectively (P = NS).

CONCLUSION

In patients with long CCL, both SES and PES were comparably effective in either angiographic or clinical long-term outcomes.