Late restenosis of the balloon-dilated site: serial angiographic observations beyond 7 years.

BACKGROUND: The present retrospective study was performed to assess the long-term (>7 years) fate of stabilized balloon-dilated sites. METHODS AND RESULTS: Between February and April 1986, 171 patients underwent successful percutaneous balloon angioplasty. Early restenosis (<1 year) occurred in 53%, but repeat balloon angioplasty stabilized the balloon-dilated site. The early period was defined as 6 months, late years as 3-5 years and long-term years as 7-12 years. Angiographic evaluation at both early year or late year periods (mean = 4.7 years) and long-term (mean = 10.4 years) periods following stabilization was available in 71 patients (94 lesions) with mean age of 61.7+/-8.5 years. Of the 71 patients 69.6% were male. Restenosis occurring after 1 year was defined as late restenosis. The mean diameter stenosis changed from 6 months (50.3+/-12.4%) to late-period (44.2 +/-13.2%; p < 0.05) and long-term period (50.3+/-16.1%; p < 0.001); but the reference vessel diameter did not change significantly. Late restenosis occurred in 28% (3-5 years) and 33% (7-12 years) of 94 lesions, and 13.8% of lesion required repeat target lesion revascularization. During this period, 5.3% of patients (5 lesions) underwent revascularization for new proximal or distal lesions. CONCLUSIONS: Decrease of luminal diameter during the early 6 months, was followed by regression after stabilization of the balloon-dilated site up to 5 years, but luminal re-narrowing occurs again over 7 years after balloon angioplasty.

Pathological analyses of long-term intracoronary Palmaz-Schatz stenting; Is its efficacy permanent?

BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability.

Long-term clinical and angiographic follow-up after coronary stent placement in native coronary arteries.

BACKGROUND: Although coronary stents have been proved effective in reducing clinical cardiac events for up to 3 to 5 years, longer term clinical and angiographic outcomes have not yet been fully clarified. METHODS AND RESULTS: To evaluate longer term (7 to 11 years) outcome, clinical and angiographic follow-up information was analyzed in 405 patients with successful stenting in native coronary arteries. Primary or secondary stabilization, which was defined as freedom from death, coronary artery bypass grafting, and target lesion-percutaneous coronary intervention (TL-PCI) during the 14 months after the initial procedure or after the last TL-PCI, was achieved in 373 patients (92%) overall. Only 7 patients (1.7%) underwent TL-PCI more than twice. After the initial 14-month period, freedom from TL-PCI reached a plateau at 84.9% to 80.7% over 1 to 8 years. However, quantitative angiographic analysis in 179 lesions revealed a triphasic luminal response characterized by an early restenosis phase until 6 months, an intermediate-term regression phase from 6 months to 3 years, and a late renarrowing phase beyond 4 years. Minimal luminal diameter in 131 patients with complete serial data were 2.62+/-0.4 mm immediately after stenting, 2.0+/-0.49 mm at 6 months, 2.19+/-0.49 mm at 3 years, and 1.85+/-0.56 mm beyond 4 years (P<0.0001). CONCLUSIONS: The efficacy and safety of coronary stenting seemed to be clinically sustained at 7 to 11 years of follow-up. However, late luminal renarrowing beyond 4 years was common, which demonstrates the need for further follow-up.

Comparison of results of coronary angioplasty for acute myocardial infarction in patients > or =75 years of age versus patients <75 years of age.

We reviewed 1,063 consecutive patients treated with direct coronary angioplasty for acute myocardial infarction (AMI): 261 were > or =75 and 802 were <75 years of age. Compared with the younger group, the older group had a higher percentage of women (48% vs 22%, p <0.0001), multivessel coronary disease (50% vs 39%, p <0.01), overall in-hospital mortality (8.4% vs 3.7%, p <0.01), cardiac mortality rate (6.1% vs 3.1%, p <0.05), and noncardiac mortality rate (2.3% vs 0.6%, p <0.05). Successful reperfusion was achieved in both groups at a similarly high rate (93% and 95%, p = NS). Hospital mortality was similar whether reperfusion was successful or failed. Successful compared with unsuccessful angioplasty decreased mortality rates in the older (6.6% vs 33%, p <0.0001) and younger (3.0% vs 18%, p <0.0001) groups. When reperfusion was successful, the cardiac mortality rate in older patients was not significantly higher than in younger patients: 4.1% vs 2.4%, p = NS.