[show abstract][hide abstract] ABSTRACT: This study aimed to characterize myocardial infarction after percutaneous coronary intervention (PCI) based on cardiac marker elevation as recommended by the new universal definition and on the detection of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR). It is also assessed whether baseline inflammatory biomarkers are higher in patients developing myocardial injury.
Cardiovascular magnetic resonance accurately assesses infarct size. Baseline C-reactive protein (CRP) and neopterin predict prognosis after stent implantation.
Consecutive patients with baseline troponin (Tn) I within normal limits and no LGE in the target vessel underwent baseline and post-PCI CMR. The Tn-I was measured until 24 h after PCI. Serum high-sensitivity CRP and neopterin were assessed before coronary angiography.
Of 45 patients, 64 (53 to 72) years of age, 33% developed LGE with infarct size of 0.83 g (interquartile range: 0.32 to 1.30 g). A Tn-I elevation >99% upper reference limit (i.e., myocardial necrosis) (median Tn-I: 0.51 μg/l, interquartile range: 0.16 to 1.23) and Tn-I > 3× upper reference limit (i.e., type 4a myocardial infarction [MI]) occurred in 58% and 47% patients, respectively. LGE was undetectable in 42% and 43% of patients with periprocedural myocardial necrosis and type 4a MI, respectively. Agreement between LGE and type 4a MI was moderate (kappa = 0.45). The levels of CRP or neopterin did not significantly differ between patients with or without myocardial injury, detected by CMR or according to the new definition (p = NS).
This study reports the lack of substantial agreement between the new universal definition and CMR for the diagnosis of small-size periprocedural myocardial damage after complex PCI. Baseline levels of CRP or neopterin were not predictive for the development of periprocedural myocardial damage.
[show abstract][hide abstract] ABSTRACT: The 2-dimensional silhouette image provided by coronary angiography has well-recognized limitations. Angiographic images do not accurately represent the true complexity of the luminal morphology in coronary disease and give no indication of the functional influence of luminal changes on coronary blood flow. These limitations are more pronounced in angiographically intermediate stenoses and in patients in whom there is a clear discrepancy between the clinical picture and angiographic findings. In such cases there is often poor concordance between the estimated percentage angiographic stenosis and the corresponding intravascular ultrasound image or noninvasive functional data. The validation and clinical availability of robust and accurate physiologic indices, which can be used as an adjunct to diagnostic angiography in the cardiac catheterization laboratory, have been pivotal in promoting ischemia-driven coronary revascularization. Deferral or revascularization based on such physiologic indices is associated with improved clinical outcome as well as more favorable health economic data. Although there are several clinical indices, fractional flow reserve remains the "gold standard," with indications for physiologic assessment of angiographic intermediate stenoses, including left main stem stenoses and ostial disease as well as serial lesions. The availability of such indices is an important step in streamlining management of patients undergoing cardiac catheterization by allowing routine provision of an "all-in-one" ischemia-driven revascularization service.
[show abstract][hide abstract] ABSTRACT: The introduction of optical coherence tomography (OCT) as an intracoronary imaging modality has allowed accurate assessment of strut apposition and neointimal tissue coverage. This study set out to assess the inter and intraobserver variability of measurements of acute stent apposition and strut tissue coverage using OCT.
Thirty patients were studied (14 immediately after stent implantation and 16 during follow-up angiography [mean of 4.7+/-2.8 months]) using OCT (LightLab, Westford, Massachusetts, US). Data analysis was performed by 2 experienced observers. Struts were classified as "embedded", "protruding" or "malapposed" to the vessel well and recorded as percentage of total struts. Intimal coverage at follow-up was measured as the thickness of tissue covering each strut expressed in mum. Intra and interobserver variability was assessed by Bland-Altman plots and by calculation of the intraclass correlation coefficient (ICC).
An average of 3967 struts was examined by each observer and, overall, 53.7% of struts was embedded, 36.4% protruding and 9.9% malapposed. Low intraobserver variability for all measures of strut apposition was found, with repeatability coefficients that ranged between 5.1% and 9.3% and ICC exceeding 95% in all cases. Interobserver variability was also low (repeatability coefficients 6.6-10.8 and ICC>91.3%). Mean intimal thickness in the follow-up group was 172.5 microm. Bland-Altman plots demonstrated a low intraobserver and interobserver variability for intimal thickness, with repeatability coefficients 26.7 mum and 24.1 mum, respectively and ICC exceeding 98.6% for both.
Low intra and interobserver variability can be expected when analyzing OCT data for stent apposition and tissue coverage. This supports the validity of OCT as a clinical and research tool in the setting of intracoronary stent imaging.
International journal of cardiology 01/2009; 141(2):151-6. · 7.08 Impact Factor
[show abstract][hide abstract] ABSTRACT: The incidence and predictors of contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) have not been specifically reported.
This retrospective analysis included all consecutive patients referred for PCI of CTO between April 2003 and March 2008, with baseline and 24 h postprocedural available creatinine levels. CIN was defined as 24 h postprocedural increase of baseline creatinine levels > or =0.5 mg/dl (CIN(05)) or > or =25% (CIN(25)). Severe renal dysfunction (SRD) was defined as acute renal failure requiring dialysis, or an increase in baseline creatinine levels > or =2.0 mg/dl (SRD(2)) or > or =50% (SRD%). Patients were classified into risk categories for CIN, according to the validated Mehran risk score.
A total of 227 patients were included, mean age of 64+/-10 years, the majority being at low risk for CIN (55% with < or =5 points in the Mehran score). CIN(25) occurred in 6.16% (14/227) patients and CIN(05) in 0.88% (2/227). The incidence of SRD(2) or SDR% was 0% (0/227) and 0.9% (2/227), respectively, with no patient requiring dialysis. Patients who developed CIN(25) received a higher contrast volume than those who did not (312 ml (210-400) vs 260 ml (200-345), p=0.14), but the difference was not statistically significant.
In this consecutive cohort of patients, the incidence of CIN following PCI for CTO was low despite the administration of moderate to large volumes of contrast media. Attempts at revascularization of CTO should not be discouraged or be prematurely interrupted because of the fear of CIN.
International journal of cardiology 01/2009; 139(1):68-74. · 7.08 Impact Factor
[show abstract][hide abstract] ABSTRACT: Drug-eluting stents (DES) have made a tremendous impact on the practice of percutaneous coronary intervention. Recently however, long-term DES failures have become a focal point, particularly with restenosis and thrombosis. An uncommon, yet important cause of DES failure is stent fracture. Of the two established first generation DES, the sirolimus-eluting stent (SES) has been particularly linked to cases of stent fracture, likely as a result of its closed cell design compared with other DES employing an open cell system. We present 2 cases of SES fracture confirmed using high-resolution intravascular optical coherence tomography giving unique insights into the in-vivo appearance of this complication.
International journal of cardiology 09/2008; 136(1):e16-20. · 7.08 Impact Factor