Persistent atrial fibrillation without the evidence of low-voltage areas: a prospective randomized trial.

BACKGROUND: An effective therapy of persistent atrial fibrillation beyond pulmonary vein isolation remains unsatisfactory. Targeting endocardial low-voltage areas represents an approach of substrate modification. This prospective, randomized study investigated the efficacy of ablation of low-voltage areas versus PVI and additional linear ablations in patients with persistent atrial fibrillation in terms of single-procedure arrhythmia-free outcome and safety. METHODS AND RESULTS: A total number of 100 patients undergoing de-novo catheter ablation for persistent AF were randomized in a 1:1 ratio into two different treatment arms: group A: pulmonary vein isolation (PVI) and, if low-voltage areas were present, a substrate modification. Group B: PVI and, if atrial fibrillation persisted, additional ablations, such as linear ablation and/or ablation of non-PV triggers. A total of 50 patients were randomized into each group without significant differences in baseline characteristics. During a mean follow-up of 17.64 ± 4.5 months after a single procedure, 34 (68%) patients of group A were free of arrhythmia recurrence versus 28 (56%) patients in group B (p = ns). In group A, 30 (60%) patients did not show endocardial fibrosis and received solely PVI. Both procedures were performed with a low number of complications; no pericardial effusion or stroke were seen in either group. CONCLUSIONS: A significant proportion of patients with persistent atrial fibrillation do not show low-voltage areas. A total of 70% of the patients receiving solely PVI did not show any recurrence of atrial fibrillation, and therefore, extensive additional ablation should be avoided in de-novo patients.

Pulmonary vein isolation using cryoballoon ablation versus RF ablation using ablation index following the CLOSE protocol: A prospective randomized trial.

BACKGROUND: The single procedure success rates of durable pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) vary between 80% and 90%. This prospective, randomized study investigated the efficacy of cryoballoon PVI (CBA) versus PVI with radio-frequency (RF)-energy following the CLOSE protocol (ablation index [AI], interlesion distance ≤6 mm, surround flow catheter) in terms of single-procedure arrhythmia-free outcome and safety. METHODS AND RESULTS: A total number of 150 patients undergoing de novo catheter ablation for paroxysmal AF were randomized to two different treatment arms. In group A patients, PVI was performed with the 23 or 28 mm cryoballoon (Artic Front™ Balloon in conjunction with an Achieve Mapping Catheter, Medtronic Inc.). The ablation procedure in group B was performed with RF-energy, using AI and following the CLOSE protocol. PVI using AI incorporates stability, contact force (CF), time, and power. The CLOSE protocol combines AI and ≤6 mm interlesion distance using a surround flow catheter (Biosense Webster Thermocool STSF). A total of 75 patients were randomized into each group without significant differences in baseline characteristics. During a mean follow-up of 12 ± 4.5 months after a single procedure, 64 (85.33%) patients of group A were free of arrhythmia recurrence versus 65 (86.67%) patients in group B (p = ns). A total of 14 patients (group A: 7 [9.33%]; group B: 7 [9.33%]; p = ns) underwent a redo-procedure. No significant difference between both groups was observed in terms of PV recovery (group A: 4 [5.33%] vs. group B: 3 [4%]; p = ns). In two patients of group A and four patients of group B, the PVs were durably isolated, whereas the patients had AF recurrence caused by extra-PV AF sources. Two patients of each group had continued paroxysmal AF but did not undergo redo-procedure. Patients of group A showed significantly more AF recurrence during the blanking period of 3 months (group A: 14 [18.67%] vs. group B: 6 [8%]; p < .05). With regard to the procedural data, the procedure time was significantly shorter in group A (70.53 ± 16.13 vs. 115.35 ± 15.38; p < .01); the flouroscopy time and dose area product showed no significant differences (Table 2). Both procedures were performed with a low number of complications; no pericardial effusion was seen in either group; in group A two patients had a significant hematoma of the groin with the need for surgical repair. CONCLUSIONS: Cryoballoon PVI and PVI using ablation index following the CLOSE protocol are equally efficient in achieving durable PV isolation. In this study, cryoballoon ablation led to significantly more AF recurrence during the blanking period.

Coronary artery spasm and impaired myocardial perfusion in patients with ANOCA: Predictors from a multimodality study using stress CMR and acetylcholine testing.

BACKGROUND: Functional coronary disorders such as coronary spasm and microvascular dysfunction (including microvascular spasm and impaired microvascular dilatation) are frequent findings among patients with angina and non-obstructed coronary arteries (ANOCA). In this study, we investigated a potential association of coronary spasm and myocardial perfusion abnormalities as well as predictors of such functional coronary disorders in ANOCA patients using a multimodality diagnostic strategy including adenosine stress CMR and intracoronary acetylcholine testing. METHODS: We enrolled 129 patients with ANOCA who underwent acetylcholine testing and adenosine stress perfusion CMR. Patients were allocated to 3 groups according to their spasm testing result with regard to standardized COVADIS criteria: 1) epicardial spasm, 2) microvascular spasm, and 3) no spasm. The myocardial perfusion reserve index (MPRI) was semiquantitatively determined from adenosine stress perfusion CMR. Multivariate regression analyses were performed to identify predictors of coronary functional disorders. RESULTS: Patients with epicardial spasm had lower MPRI than patients without, whereas MPRI was preserved in patients with microvascular spasm. Multivariate analyses revealed age, previous myocardial infarction, LVEF and epicardial spasm as independent predictors of diminished MPRI, whereas previous PCI was associated with epicardial spasm, and female sex was a strong predictor of microvascular spasm. CONCLUSIONS: Our results demonstrate coexistence of different functional coronary disorder endotypes involving the macro- and microvascular level of the coronary circulation in patients with ANOCA. We demonstrate that epicardial spasm is associated with diminished myocardial perfusion reserve and report further predictors of coronary functional disorders.

Improved durable pulmonary vein isolation with shorter procedure times and lower energy levels using RF ablation with ablation index and a stringent lesion contiguity.

BACKGROUND: The single procedure success rates of durable pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) varies between 80 and 90%. Ablation index, incorporating contact force, stability, time and power is a more profound parameter of significant lesion size and has been established. Equally important is a stringent contiguity of the lesion set. METHODS AND RESULTS: A total number of 100 consecutive patients undergoing de-novo catheter ablation for paroxysmal atrial fibrillation (PAF) were analyzed between 2016 and 2019. In the first 50 patients (group A) PVI was performed using a surround flow, contact force catheter (Biosense Webster Thermocool STSF, Biosense Webster, USA) with a drag-and-ablate technique to encircle the PVs. In the following 50 patients (group B), PVI was performed using ablation index and a stringent lesion contiguity with an interlesion distance (ILD) of <5 mm. The baseline characteristics showed no significant differences between both groups. During a mean follow-up of 18 ± 3 months after a single procedure, 36 (72%) patients of group A were free of arrhythmia recurrence versus 43 (86%) patients in group B (p = 0.047). A total of 14 patients (group A: 10 (20%), group B: 4 (8%); underwent a redo-procedure. 7 patients of group A (14%) and 2 patients of group B (4%) showed recovered veins. In 3 patients of group A and 2 patients of group B the PVs were durably isolated. In these patients persistent AF recurrence was caused by extra-PV AF sources. Four patients of group A and three patients of group B had continued paroxysmal or persistent AF but did not undergo redo-procedure. With regard to the procedural data, the procedure time, the total energy and the fluoroscopy time were significantly lower in group B (AI and ILD <5 mm) (128.86 ± 18.19 versus 115.35 ± 15.38; p < 0.05; 1619.16 ± 988.56 versus 1186.26 ± 756.34; p < 0.05; 11.49 ± 3.20 versus 9.66 ± 3.86; p = 0.04). Both procedures were performed with a low number of complications, no pericardial effusion was seen in either group. CONCLUSIONS: PVI using ablation index in combination with a stringent lesion contiguity improves clinical outcome after first-time PVI with lower PVI recovery, shorter procedure times, lower total energy and shorter fluoroscopy times and therefore, is more efficient.

Assessment of coronary vasomotor responses to acetylcholine in German and Japanese patients with epicardial coronary spasm-more similarities than differences?

Coronary spasm is an established cause for angina pectoris. Ethnic differences have been suggested among Asian compared to Caucasian patients regarding prevalence, gender distribution, and angiographic patterns of coronary spasm. The aim of this study was to compare contemporary German and Japanese patients with coronary spasm. Between 2011 and 2015, 149 patients with resting angina and unobstructed coronary arteries with acetylcholine-induced epicardial spasm were enrolled in Stuttgart, Germany (n = 69) and Sendai, Japan (n = 80). All patients underwent intracoronary acetylcholine testing according to a standardized protocol. Comprehensive analysis included type of spasm (focal/diffuse), dose of acetylcholine leading to spasm, and frequency of multivessel spasm. Patients in this study were 61 ± 11 years old, predominantly female (54%), and had normal left ventricular ejection fraction (73 ± 9%). Diffuse spasm was the most prevalent type of spasm (85%) whereas focal spasm was found in the remaining 15% of patients. 31% of patients had multivessel spasm. Comparing the German with the Japanese patients, distribution of spasm type (focal/diffuse, p = 0.19) and frequency of multivessel spasm (p = 0.22) were comparable. Moreover, when Japanese patients were compared with German patients and diffuse spasm with focal spasm patients, respectively, no significant differences were observed regarding the acetylcholine dose required to induce spasm (p = 0.078 and p = 0.46, respectively). In conclusion, diffuse epicardial coronary spasm is the most frequent finding among German and Japanese patients with resting angina, unobstructed coronary arteries, and epicardial spasm on acetylcholine testing. Japanese and German patients share several similarities including comparable types of spasm and frequency of multivessel spasm.

Different vasoreactivity of arterial bypass grafts versus native coronary arteries in response to acetylcholine.

BACKGROUND: Coronary angiography is often performed in patients with recurrent angina after successful coronary artery bypass grafting (CABG) in search of the progression of atherosclerosis. However, in many of these patients, no relevant stenosis can be detected. We speculate that coronary spasm may be associated with angina in these patients. METHODS: From 2307 patients with unobstructed coronaries who underwent intracoronary acetylcholine spasm provocation testing (ACh-test) between 2012 and 2016, 54 consecutive patients who fulfilled the following inclusion criteria were included in this cohort study: previous left internal thoracic artery (LITA) bypass on the left anterior descending (LAD) coronary artery, ongoing/recurrent angina pectoris, no significant (< 50%) coronary artery or bypass stenosis. In all participants, the ACh-test was performed via the LITA bypass. RESULTS: In 14 patients (26%) the ACh-test elicited epicardial spasm of the LAD distal to the anastomosis (≥ 90% diameter reduction with reproduction of the patient's symptoms and ischemic ECG shifts). Microvascular spasm (reproduction of symptoms and ischemic ECG-changes but no epicardial spasm) was seen in 30 patients (55%). The ACh-test was normal in the remaining 10 patients (19%). ACh-testing did not elicit any relevant vasoconstriction in the LITA bypasses in contrast to the LAD on quantitative coronary analyses (4.89 ± 7.36% vs. 52.43 ± 36.07%, p < 0.01). CONCLUSION: Epicardial and microvascular coronary artery spasm are frequent findings in patients with ongoing or recurrent angina after CABG but no relevant stenosis. Vasoreactivity to acetylcholine is markedly different between LITA bypasses and native LAD arteries with vasoconstriction almost exclusively occurring in the LAD.

Long-Term Follow-Up in Patients With Stable Angina and Unobstructed Coronary Arteries Undergoing Intracoronary Acetylcholine Testing.

OBJECTIVES: The aim of this study was to investigate the prognosis of a large cohort of patients with stable angina and unobstructed coronaries undergoing acetylcholine spasm testing. BACKGROUND: Coronary artery spasm can be found in up to 60% of patients with symptoms of myocardial ischemia despite unobstructed coronary arteries. METHODS: Consecutive symptomatic patients with unobstructed coronary arteries undergoing acetylcholine testing to detect epicardial or microvascular coronary spasm were prospectively enrolled. After a median follow-up period of 7.2 years (6.5 to 7.9 years), data regarding mortality, nonfatal myocardial infarction, stroke, repeat coronary angiography, recurrent symptoms, and quality of life were obtained in 736 patients (57% women, mean age 62 ± 12 years). RESULTS: In total, 55 deaths (7.5%), 8 nonfatal myocardial infarctions (1.4%), and 12 strokes (2.2%) occurred during the follow-up period. Recurrent symptoms were reported by 64% of patients, and repeat coronary angiography was performed in 12% of cases. Multivariate analysis revealed epicardial spasm as a predictor of nonfatal myocardial infarction (hazard ratio: 14.469; 95% confidence interval: 1.735 to 120.646) and repeat angiography (hazard ratio: 1.703; 95% confidence interval: 1.062 to 2.732), whereas patients with microvascular spasm more often had recurrent angina at follow-up (hazard ratio: 1.311; 95% confidence interval: 1.013 to 1.697). CONCLUSIONS: In this long-term follow-up study, the overall prognosis of patients with coronary spasm was favorable. Patients with epicardial spasm were at increased risk for myocardial infarction and repeat angiography, while microvascular spasm was associated with recurrent angina. Acetylcholine testing may help identify patients at increased risk for adverse cardiac events among this overall low-risk population.

Prognostic implications of coronary artery stenosis and coronary spasm in patients with stable angina: 5-year follow-up of the Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries (ACOVA) study.

BACKGROUND: In the Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries study, we showed that 62% of patients with stable angina and unobstructed coronary arteries had coronary spasm. In this study, we sought to assess the 5-year prognosis in these patients. METHODS: Data regarding the following endpoints were obtained: death, non-fatal myocardial infarction, coronary event (=cardiac death or non-fatal myocardial infarction), persistent angina and repeated coronary angiography. Quality of life was assessed using the Seattle Angina Questionnaire. RESULTS: Among patients with unobstructed coronary arteries there were three deaths (2.9%) and no non-fatal myocardial infarction. Among those with obstructive CAD 15 died (13.8%) and three had a non-fatal myocardial infarction (2.8%). Patients with obstructive CAD had a higher rate of all-cause death and coronary events compared to those without (P = 0.004). Persistent angina was more prevalent in patients with unobstructed coronaries (P = 0.042). Prognosis of patients with unobstructed coronaries regarding hard clinical events, persistent angina and repeated coronary angiography was independent of the presence of coronary spasm (all P > 0.05). However, spasm patients were more likely to take nitrate medication at follow-up (P = 0.029). CONCLUSION: Patients with stable angina and unobstructed coronary arteries have a favorable prognosis regarding mortality and non-fatal myocardial infarction after 5 years compared to patients with obstructive CAD irrespective of the presence of coronary artery spasm. However, persistent angina remains a common issue in patients with unobstructed coronary arteries leading to a similar frequency of repeated invasive procedures as in patients with obstructive CAD.

Microvascular spasm in non-ST-segment elevation myocardial infarction without culprit lesion (MINOCA).

BACKGROUND: Up to 30% of patients with acute coronary syndrome have no culprit lesion. Coronary microvascular spasm is an alternative cause for such a clinical presentation. However, this has rarely been investigated systematically. The aim of our study was to assess the frequency of coronary microvascular spasm in patients with NSTEMI without culprit lesion (MINOCA) by intracoronary acetylcholine testing (ACH-test). METHODS: Between 2014 and 2017, 940 patients with NSTEMI underwent coronary angiography and 125 (13%) had no culprit lesion (< 50% stenosis on visual assessment). Of the latter, 29 patients had other causes for the clinical presentation (e.g. tako-tsubo-syndrome or myocarditis). The remaining 96 patients were recruited for the study and underwent ACH-testing according to a standardized protocol. RESULTS: The ACH-test was normal in 40 (42%) and abnormal in the remaining 56 (58%) patients. Of the latter, 26 patients (46%) had epicardial spasm (epicardial narrowing ≥ 90%, reproduction of symptoms and ischemic ST-segment changes) and 30 (54%) microvascular spasm (ischemic ST-shifts and angina without epicardial vasoconstriction ≥ 90%). The peak high-sensitive troponin-T concentration was 113 (42-255) pg/ml. Patients with coronary spasm had more often a positive family history compared to those without and patients with epicardial compared to microvascular spasm were more often smokers. CONCLUSION: Coronary microvascular spasm is frequently found in patients with NSTEMI without culprit lesion and represents a likely cause of myocardial injury. ACH-testing is useful for detection of vasomotor disorders allowing tailored treatment with calcium antagonists and/or nitrates in addition to secondary prevention to improve symptoms and prognosis. Microvascular spasm in non-ST-segment elevation myocardial infarction without culprit lesion (MINOCA) .

Impact of baseline calibration on semiquantitative assessment of myocardial perfusion reserve by adenosine stress MRI.

In this study, we sought to investigate the impact of baseline calibration, which is used in quantitative cardiac MRI perfusion analysis to correct for surface coil inhomogeneity and noise, on myocardial perfusion reserve index (MPRI) and its contribution to previously reported paradoxical low MPRI < 1.0 in patients with unobstructed coronary arteries. Semiquantitative perfusion analysis was performed in 20 patients with unobstructed coronary arteries undergoing stress/rest perfusion CMR and in ten patients undergoing paired rest perfusion CMR. The following baseline calibration settings were compared: (1) baseline division, (2) baseline subtraction and (3) no baseline calibration. In uncalibrated analysis, we observed ~ 20% segmental dispersion of signal intensity (SI)-over-time curves. Both baseline subtraction and baseline division reduced relative dispersion of t0-SI (p < 0.001), but only baseline division corrected for dispersion of peak-SI and maximum upslope also (p < 0.001). In the assessment of perfusion indices, however, baseline division resulted in paradoxical low MPRI (1.01 ± 0.23 vs. 1.63 ± 0.38, p < 0.001) and rest perfusion index (RPI 0.54 ± 0.07 vs. 0.94 ± 0.12, p < 0.001), respectively. This was due to a reversed ratio of blood-pool and myocardial baseline-SI before the second perfusion study caused by circulating contrast agent from the first injection. In conclusion, baseline division reliably corrects for inhomogeneity of the surface coil sensitivity profile facilitating comparisons of regional myocardial perfusion during hyperemia or at rest. However, in the assessment of MPRI, baseline division can lead to paradoxical low results (even MPRI < 1.0 in patients with unobstructed coronary arteries) potentially mimicking severely impaired perfusion reserve. Thus, in the assessment of MPRI we propose to waive baseline calibration.

Epicardial Coronary Spasm in Women With Angina Pectoris and Unobstructed Coronary Arteries Is Linked With a Positive Family History: An Observational Study.

PURPOSE: Coronary spasm is frequently found in patients with angina and unobstructed coronaries. The pathophysiology is incompletely understood, although sex differences have been described. Often a positive family history (PFH) is encountered. We assessed the relationship between sex, coronary spasm, and a PFH for cardiovascular disease. METHODS: This single-center observational study recruited 415 stable angina patients with unobstructed coronaries (no stenosis >50%) between 2008 and 2011 (mean [SD] age, 62 [10] years; 38% men). Patients were referred for angiography because of signs and symptoms of myocardial ischemia. Intracoronary acetylcholine (ACh) testing was performed in all patients according to a standardized protocol. Risk factor assessment included hypertension, hypercholesterolemia, diabetes, smoking, and a PFH. The latter was defined as a first-degree relative with myocardial infarction or stroke. Statistical analysis involved comparison of categorical and continuous variables. Multivariable analysis aimed at identifying predictors for a pathologic ACh testing, microvascular spasm, and a PFH. FINDINGS: Epicardial spasm was found in 33% of patients and microvascular spasm in 30% of patients. A pathologic ACh test was more frequent in women than in men (72% vs 49%; P < 0.0005). A PFH was found in 55% of patients with significantly more women than men (61% vs 45%; P = 0.001). Among patients with epicardial spasm, women had a PFH significantly more often than men (66% vs 43%; P = 0.006). The latter difference was not found when comparing women and men with microvascular spasm. IMPLICATIONS: There is a female preponderance among patients with angina and unobstructed coronaries. ACh testing enables detection of coronary spasm. Epicardial spasm in women is associated with a PFH.

Impact of drug-eluting balloon (pre- or post-) dilation on neointima formation in de novo lesions treated by bare-metal stent: the IN-PACT CORO trial.

UNLABELLED: The efficacy of DEB in modifying the high restenosis risk associated with BMS implantation is doubtful. Optical coherence tomography (OCT) may allow precise assessment of neointimal formation after stent implantation. We performed a single-center, prospective, 1:2 randomized trial comparing BMS implantation alone (BMS group) vs. additional DEB (DEB group). DEB patients were further randomized 1:1 to DEB before stenting (pre-DEB group), or after stenting (post-DEB group). Primary endpoint was OCT-assessed neointimal hyperplasia (expressed both as mean in-stent neointimal area and as percentage obstruction of the mean stent area) at 6 months. Secondary endpoints were the percentage of uncovered and malapposed stent struts. Thirty patients were enrolled and randomized to BMS (n = 10), pre-DEB (n = 10), post-DEB (n = 10). At 6-month OCT follow-up, DEB significantly reduced neointimal area compared with BMS: mean neointimal area 2.01 ± 0.89 vs. 3.03 ± 1.07 mm(2) (p = 0.02), percentage area obstruction 24.56 ± 12.50 vs. 37.51 ± 12.26 % (p = 0.02). The percentage of uncovered and malapposed stent struts did not differ significantly between BMS and DEB. In the comparison between pre-DEB and post-DEB, no significant difference was observed for both primary and secondary endpoints. In de novo coronary lesions treated with BMS, DEB use could be associated with a mild reduction in neointimal hyperplasia at 6 months; this effect could be unrelated to the timing of DEB dilation (pre- or post-stenting). CLINICAL TRIAL REGISTRATION INFORMATION: http://www.clinicaltrials.gov . Identifier: NCT01057563.

Trends and Outcomes of Radial Approach in Left-Main Bifurcation Percutaneous Coronary Intervention in the Drug-Eluting Stent Era: A Two-Center Registry.

OBJECTIVE: To analyze the immediate and long-term outcomes of transradial (TR) percutaneous coronary intervention (PCI) to unprotected left main stem (ULMS) bifurcation and to assess the main aspects affecting access-site choice in this specific PCI setting. BACKGROUND: TR-PCI to the ULMS is feasible, but data specifically comparing TR and transfemoral (TF) approaches in ULMS-bifurcation PCI are limited. METHODS: We set up a two-center (Rome, Italy and Oxford, United Kingdom) retrospective registry aimed at comparing the immediate and 1-year outcomes of consecutive patients who underwent ULMS-bifurcation PCI with drug-eluting stent implantation from 2005 to 2013 using the TF or TR approach. Clinical endpoints were: total mortality; major adverse cardiac and cerebrovascular event (MACCE) rate; and net adverse clinical event (NACE) rate. RESULTS: A total of 467 patients undergoing ULMS-bifurcation PCI were enrolled (221 TF and 244 TR). TR approach was increasingly adopted over time for both simple and complex procedures. No significant differences were observed between the TR and TF groups in terms of 1-year mortality (10.7% vs 9.8%; P=.79) and MACCE (18.2% vs 15.2%; P=.44). TR patients, as compared with TF, had significantly fewer access-site complications (2.0% vs 6.3% in TF; P=.02), resulting in a significant reduction of NACE rate (6.9% vs 15.7;%; P=.01). CONCLUSION: In patients undergoing ULMS-bifurcation PCI, the selection of TR instead of TF approach is associated with similar early and long-term ischemic complications and with a significant reduction of access-site complications, resulting in lower NACE rate.

Clinical and procedural impact of aortic arch anatomic variants in carotid stenting procedures.

OBJECTIVES: To evaluate the impact of aortic arch variants in patients undergoing carotid artery stenting (CAS). BACKGROUND: CAS is increasingly carried out to treat the patients with internal carotid artery (ICA) stenosis. Aortic arch anatomy may influence its feasibility and affect clinical outcome. METHODS: Aortic arch digital subtraction angiography was systematically performed before CAS. Aortic arch elongation and bovine arch variants were recorded. Catheter manipulation time (CMT) was assessed for each patient. Adverse cardiovascular and cerebral events were assessed at 30 days. RESULTS: A total of 282 consecutive patients undergoing CAS under proximal balloon occlusion (57.8%) or distal filter (42.2%) neuroprotection were enrolled (age, 72 ± 7 years; 72.7% males). Type II and III elongation variants were detected in 23.4% and 10.6% of patients, respectively; in total, 20.5% of the patients had bovine configuration. CMT was significantly influenced by aortic elongation (56.1 ± 16.5 min in patients with type III aortic arch configuration compared to 38.2 ± 11.6 min in patients with type I or type II, P < 0.01) and (in left ICA) by bovine configuration (49.2 ± 11.4 min in bovine variants vs. 37.7 ± 11.5 min in patients with nonbovine anatomy, P < 0.001). CMT, but not aortic arch anatomy, resulted the only independent predictor of 30-day adverse outcome (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.03-1.10, P < 0.01). CONCLUSIONS: Adverse aortic arch anatomies are frequently encountered in CAS procedures and are associated to longer procedural times. A longer CMT increases the risk for adverse outcome. These data suggest that a careful procedure planning aimed at a reduction of CMT may be pivotal to improve the safety of CAS procedures.

Frequency domain optical coherence tomography to assess non-ostial left main coronary artery.

AIMS: The aim of this study was to assess the feasibility of unprotected non-ostial left main (LM) imaging by frequency domain optical coherence tomography (FD-OCT). METHODS AND RESULTS: We conducted a retrospective analysis of OCT studies performed to image lesions located in the non-ostial LM. OCT studies were analysed off-line to detect the number of artefact frames in the different LM/bifurcation segments. OCT cross-sectional images were used to assess area measures. OCT longitudinal reconstructions were used to obtain the LM length. Standard quantitative coronary angiography (QCA) was used as the reference methodology. A total of 54 patients with non-ostial LM disease entered the study. The mean number of LM artefact frames was 8±10, corresponding to 19% of the total number of LM frames analysed. The percentages of artefact frames differed significantly according to the segment analysed: 43.3% proximal LM, 11.4% mid LM and 2.1% distal LM, 2.0% ostial left anterior descending artery and 0% ostial left circumflex artery (p<0.0001). All LM OCT measurements were significantly correlated with QCA measurements. CONCLUSIONS: The results of the present study show that FD-OCT assessment of non-ostial LM disease is feasible and may provide high-quality imaging. OCT assessment of distal LM is more efficient than that of the proximal LM segment.

Dual role of circulating endothelial progenitor cells in stent struts endothelialisation and neointimal regrowth: a substudy of the IN-PACT CORO trial.

BACKGROUND: Endothelialisation is a crucial event after percutaneous coronary intervention (PCI). Endothelial progenitor cells (EPCs) are bone marrow derived elements with reparative properties. We aimed to assess the relationship between circulating EPC levels and stent neointimal hyperplasia (NIH) using frequency domain optical coherence tomography (FD-OCT). METHODS: Patients undergoing elective PCI to native vessels and randomised to bare metal stent (BMS) alone versus BMS plus drug coated balloon (DCB) were included. At six months, angiographic follow-up and FD-OCT were performed to measure percentage neointimal hyperplasia volume obstruction (%NIHV), and percentage of uncovered stent struts (%US). Venous blood samples were obtained before the procedure and at six months to detect CD34+CD45dimKDR+ EPC levels. RESULTS: Twenty patients were enrolled. A significant relationship was observed between baseline EPC levels and %NIHV (R: 0.63, p: 0.03) and %US (R: -0.56, p: 0.01) at follow-up. Both EPC levels and DCB use were independently related to %NIHV (ß: 0.55; p < 0.001 and ß: -0.51; p: 0.001, respectively), while only EPC levels were independently associated to %US (ß: -0.52; p: 0.01). Higher %NIHV (p: 0.004) and lower %US (p: 0.005) were observed in patients with stable or increasing EPC level. CONCLUSION: Our study shows a relationship between EPC levels and stent strut coverage, supporting a dual role for these cells in favouring stent endothelialisation but also NIH growth.

Fractional flow reserve or optical coherence tomography guidance to revascularize intermediate coronary stenosis using angioplasty (FORZA) trial: study protocol for a randomized controlled trial.

BACKGROUND: The management of patients with angiographically intermediate coronary lesions is a major clinical issue. Fractional flow reserve provides validated functional insights while optical coherence tomography provides high resolution anatomic imaging. Both techniques may be applied to guide management in case of angiographically intermediate coronary lesions. Moreover, these techniques may be used to optimize the result of percutaneous coronary intervention. We aim to compare the clinical and economic impact of fractional flow reserve versus optical coherence tomography guidance in patients with angiographically intermediate coronary lesions. METHODS/DESIGN: Patients with at least one angiographically intermediate coronary lesion will be randomized (ratio 1:1) to fractional flow reserve or optical coherence tomography guidance. In the fractional flow reserve arm, percutaneous coronary intervention will be performed if fractional flow reserve value is ≤0.80, and will be conducted with the aim of achieving a post-percutaneous coronary intervention fractional flow reserve target value of ≥0.90. In the optical coherence tomography arm, percutaneous coronary intervention will be performed if percentage of area stenosis (AS%) is ≥75% or 50 to 75% with minimal lumen area <2.5 mm2, or if a major plaque ulceration is detected. In case of percutaneous coronary intervention, optical coherence tomography will guide the procedure in order to minimize under-expansion, malapposition, and edge dissections.Cost load and clinical outcome will be prospectively assessed at one and thirteen months. The assessed clinical outcome measures will be: major cardiovascular events and occurrence of significant angina defined as a Seattle Angina Questionnaire score <90 in the angina frequency scale. DISCUSSION: The FORZA trial will provide useful guidance for the management of patients with coronary artery disease by prospectively assessing the use of two techniques representing the gold standard for functional and anatomical definition of coronary plaques. TRIAL REGISTRATION: Clinicaltrials.gov NCT01824030.

Radial artery complications occurring after transradial coronary procedures using long hydrophilic-coated introducer sheath: a frequency domain-optical coherence tomography study.

This study was performed to analyze the impact of transradial intervention (TRI), performed by long (25-cm) hydrophilic-coated radial introducer sheath (HRS), on radial artery (RA). Both acute damages and chronic intimal modifications, occurring in RA, were assessed using frequency domain-optical coherence tomography (FD-OCT). FD-OCT evaluation of RA was performed in 51 consecutive patients, undergoing TRI by long (25-cm) HRS. FD-OCT was performed from RA ostium to the puncture site. Acute damages such as intimal tears and medial dissections together with chronic intimal modifications, assessed as intimal hyperplasia indexes, were observed and compared between proximal and distal RA segments. Intimal tears were detected in 37% of patients, especially located in proximal RA segment (p = 0.09). Medial dissections were imaged in 9.8% of patients with no significant difference between proximal and distal RA segments. Intimal hyperplasia indexes were higher in distal RA segment, with no significant association with a previous history of TRI. In the setting of TRI, performed by long HRS, intimal tears represented the main RA injury occurring in about one-third of patients, while medial dissections only occurred in a small proportion of patients. Distal RA segment was more prone to intimal thickening, although this phenomenon was not associated with repeated transradial procedures.

Frequency-domain optical coherence tomography findings in patients with bifurcated lesions undergoing provisional stenting.

AIMS: Bifurcations represent challenging lesions which may benefit from improved understanding of stent-related vessel complications. Since optical coherence tomography (OCT) allows us to detect post-stenting vessel injuries, we sought to assess the geographic pattern of stent-related complications occurring during provisional stenting of bifurcated lesions. METHODS AND RESULTS: Fifty-one patients with bifurcated lesions treated by provisional stenting and undergoing intra-procedural OCT assessment were enrolled. OCT images were acquired with the aim of guiding the percutaneous coronary intervention but were re-analysed off-line for the present study. The stented bifurcation was divided into four segments [three in the main vessel (MV) and one in the side branch (SB)]. The following acute post-stenting vessel injuries/complications at the different bifurcation segments were evaluated: (i) stent under-expansion, (ii) stent malapposition, (iii) stent edge dissection, (iv) side-branch ostium dissection, (v) tissue prolapse, (vi) intracoronary thrombus, and (vii) in-stent dissection. A total of 55 bifurcation lesions undergoing provisional stenting were analysed. At least one OCT complication was detectable in all cases. Across different bifurcation sites, significant differences in the occurrence of stent complications were observed. In particular, stent malapposition was more common at the proximal MV segment (P < 0.001), while tissue prolapse was more common at the distal MV segment (P < 0.001). CONCLUSION: In bifurcated interventions, OCT often detects vessel injuries/stent complications, which tend to have a specific geographical distribution. In particular, stent malapposition is more common at the proximal MV and tissue prolapse at the distal MV segment.