Mechanisms of balloon angioplasty and repeat stenting in patients with drug-eluting in-stent restenosis

BACKGROUND

Mechanisms of lumen gain during reinterventions in patients with drug-eluting stent (DES) in-stent restenosis (ISR) remain unsettled.

METHODS

We sought to assess the mechanisms of acute lumen gain after balloon angioplasty (BA) and repeat drug-eluting stent (DES) implantation in patients with DES-ISR. Following a prospective protocol 29 consecutive patients with DES-ISR were sequentially treated with BA and new DES implantation under a multimodality intracoronary imaging assessment including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Imaging studies were systematically obtained, at baseline, after BA, and after DES. Results of interventions were compared using volumetric and morphometric (ISR pattern and injury score) analyses.

RESULTS

IVUS and OCT demonstrated that acute lumen gain after BA and DES equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation not only increased final lumen (baseline 39.6±18.5mm(3), post-BA 58.6±26.6mm(3), post-DES 84.2±30.8mm(3), all p<0.001) but also provided a smoother lumen (injury score 1.57±0.86 vs 0.22±0.26, p<0.001). At the 9th month of angiographic follow-up (86% patients) in-stent late loss was 0.44±0.5mm and 4 patients (16%) developed ISR. The ISR pattern on OCT was not associated with the injury score after interventions or late angiographic findings. Likewise, the injury score did not predict late angiographic outcome.

CONCLUSIONS

In patients with DES ISR, lumen gain equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation provides a larger and smoother coronary lumen.

Spontaneous coronary artery dissection: long-term follow-up of a large series of patients prospectively managed with a "conservative" therapeutic strategy

OBJECTIVES

This study sought to assess the long-term clinical outcome of patients with spontaneous coronary artery dissection (SCD) managed with a conservative strategy.

BACKGROUND

SCD is a rare, but challenging, clinical entity.

METHODS

A prospective protocol, including a conservative management strategy, was followed. Revascularization was only considered in cases with ongoing/recurrent ischemia. Inflammatory/immunologic markers were systematically obtained.

RESULTS

Forty-five consecutive patients (incidence 0.27%) were studied during a 6-year period. Of these, 27 patients (60%) had "isolated" SCD (I-SCD), and 18 had SCD associated with coronary artery disease (A-SCD). Age was 53 ± 11 years, and 26 patients were female. Most patients presented with an acute myocardial infarction. SCD had a diffuse angiographic pattern (length: 31 ± 23 mm). In 11 patients, the diagnosis was confirmed by intracoronary imaging techniques. Sixteen patients (35%) required revascularization during initial admission. One patient died after surgery, but no additional patient experienced recurrent myocardial infarction. No significant inflammatory/immunologic abnormalities were detected. At follow-up (median 730 days), only 3 patients presented with adverse events (1 died of congestive heart failure, and 2 required revascularization). No patient experienced a myocardial infarction or died suddenly. Event-free survival was similar (94% and 88%, respectively) in patients with I-SCD and A-SCD. Notably, at angiographic follow-up, spontaneous "disappearance" of the SCD image was found in 7 of 13 (54%) patients.

CONCLUSIONS

In this large prospective series of consecutive patients with SCD, a "conservative" therapeutic strategy provided excellent long-term prognosis. Clinical outcome was similar in patients with I-SCD and A-SCD. The natural history of SCD includes spontaneous healing with complete resolution.

Diagnosis of spontaneous coronary artery dissection by optical coherence tomography

OBJECTIVES

This study sought to assess the diagnostic value of optical coherence tomography (OCT) in patients with suspected spontaneous coronary artery dissection (SCAD).

BACKGROUND

SCAD is a rare but challenging clinical entity.

METHODS

Following a prospective protocol, OCT was performed in 17 consecutive patients with a clinical and angiographic suspicion of SCD from a total of 5,002 patients undergoing coronary angiography. A conservative management strategy was followed.

RESULTS

OCT ruled out the diagnosis of SCAD in 6 patients with coronary artery disease (atherosclerotic plaques and/or intracoronary thrombus). In 11 patients (age 48 ± 9 years, 9 female), OCT confirmed the presence of SCAD. A double-lumen or intramural hematoma image was visualized in all cases. However, only 3 patients presented an intimal "flap" on angiography. OCT readily identified the intimal rupture site (n = 7), the thickness (348 ± 84 μm) and length (31 ± 9 mm) of the intimomedial membrane, the area of the true (1.1 ± 0.5 mm(2)) and false lumen (5.9 ± 2.1 mm(2)), the associated intramural hematoma (n = 9), and thrombi in the true or false lumens (n = 11). Most of these findings were angiographically silent. After stenting (n = 4), OCT disclosed adequate stent coverage, expansion, and apposition, but also residual intramural hematoma at the stented site (abluminal) and at the distal vessel.

CONCLUSIONS

OCT provides unique insights in patients with SCAD that allow an early diagnosis and adequate management. Most of these findings are undetectable by angiography.