Efficacy of a device to narrow the coronary sinus in refractory angina.

BACKGROUND: Many patients with coronary artery disease who are not candidates for revascularization have refractory angina despite standard medical therapy. The balloon-expandable, stainless steel, hourglass-shaped, coronary-sinus reducing device creates a focal narrowing and increases pressure in the coronary sinus, thus redistributing blood into ischemic myocardium. METHODS: We randomly assigned 104 patients with Canadian Cardiovascular Society (CCS) class III or IV angina (on a scale from I to IV, with higher classes indicating greater limitations on physical activity owing to angina) and myocardial ischemia, who were not candidates for revascularization, to implantation of the device (treatment group) or to a sham procedure (control group). The primary end point was the proportion of patients with an improvement of at least two CCS angina classes at 6 months. RESULTS: A total of 35% of the patients in the treatment group (18 of 52 patients), as compared with 15% of those in the control group (8 of 52), had an improvement of at least two CCS angina classes at 6 months (P=0.02). The device was also associated with improvement of at least one CCS angina class in 71% of the patients in the treatment group (37 of 52 patients), as compared with 42% of those in the control group (22 of 52) (P=0.003). Quality of life as assessed with the use of the Seattle Angina Questionnaire was significantly improved in the treatment group, as compared with the control group (improvement on a 100-point scale, 17.6 vs. 7.6 points; P=0.03). There were no significant between-group differences in improvement in exercise time or in the mean change in the wall-motion index as assessed by means of dobutamine echocardiography. At 6 months, 1 patient in the treatment group had had a myocardial infarction; in the control group, 1 patient had died and 3 had had a myocardial infarction. CONCLUSIONS: In this small clinical trial, implantation of the coronary-sinus reducing device was associated with significant improvement in symptoms and quality of life in patients with refractory angina who were not candidates for revascularization. (Funded by Neovasc; COSIRA ClinicalTrials.gov number, NCT01205893.).

Coronary bifurcation lesions treated with simple or complex stenting: 5-year survival from patient-level pooled analysis of the Nordic Bifurcation Study and the British Bifurcation Coronary Study.

AIMS: Randomized trials of coronary bifurcation stenting have shown better outcomes from a simple (provisional) strategy rather than a complex (planned two-stent) strategy in terms of short-term efficacy and safety. Here, we report the 5-year all-cause mortality based on pooled patient-level data from two large bifurcation coronary stenting trials with similar methodology: the Nordic Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study: old, new, and evolving strategies (BBC ONE). METHODS AND RESULTS: Both multicentre randomized trials compared simple (provisional T-stenting) vs. complex (culotte, crush, and T-stenting) techniques, using drug-eluting stents. We analysed all-cause death at 5 years. Data were collected from phone follow-up, hospital records, and national mortality tracking. Follow-up was complete for 890 out of 913 patients (97%). Both Simple and Complex groups were similar in terms of patient and lesion characteristics. Five-year mortality was lower among patients who underwent a simple strategy rather than a complex strategy [17 patients (3.8%) vs. 31 patients (7.0%); P = 0.04]. CONCLUSION: For coronary bifurcation lesions, a provisional single-stent approach appears to be associated with lower long-term mortality than a systematic dual stenting technique.

18F-fluoride positron emission tomography for identification of ruptured and high-risk coronary atherosclerotic plaques: a prospective clinical trial.

BACKGROUND: The use of non-invasive imaging to identify ruptured or high-risk coronary atherosclerotic plaques would represent a major clinical advance for prevention and treatment of coronary artery disease. We used combined PET and CT to identify ruptured and high-risk atherosclerotic plaques using the radioactive tracers (18)F-sodium fluoride ((18)F-NaF) and (18)F-fluorodeoxyglucose ((18)F-FDG). METHODS: In this prospective clinical trial, patients with myocardial infarction (n=40) and stable angina (n=40) underwent (18)F-NaF and (18)F-FDG PET-CT, and invasive coronary angiography. (18)F-NaF uptake was compared with histology in carotid endarterectomy specimens from patients with symptomatic carotid disease, and with intravascular ultrasound in patients with stable angina. The primary endpoint was the comparison of (18)F-fluoride tissue-to-background ratios of culprit and non-culprit coronary plaques of patients with acute myocardial infarction. FINDINGS: In 37 (93%) patients with myocardial infarction, the highest coronary (18)F-NaF uptake was seen in the culprit plaque (median maximum tissue-to-background ratio: culprit 1·66 [IQR 1·40-2·25] vs highest non-culprit 1·24 [1·06-1·38], p<0·0001). By contrast, coronary (18)F-FDG uptake was commonly obscured by myocardial uptake and where discernible, there were no differences between culprit and non-culprit plaques (1·71 [1·40-2·13] vs 1·58 [1·28-2·01], p=0·34). Marked (18)F-NaF uptake occurred at the site of all carotid plaque ruptures and was associated with histological evidence of active calcification, macrophage infiltration, apoptosis, and necrosis. 18 (45%) patients with stable angina had plaques with focal (18)F-NaF uptake (maximum tissue-to-background ratio 1·90 [IQR 1·61-2·17]) that were associated with more high-risk features on intravascular ultrasound than those without uptake: positive remodelling (remodelling index 1·12 [1·09-1·19] vs 1·01 [0·94-1·06]; p=0·0004), microcalcification (73% vs 21%, p=0·002), and necrotic core (25% [21-29] vs 18% [14-22], p=0·001). INTERPRETATION: (18)F-NaF PET-CT is the first non-invasive imaging method to identify and localise ruptured and high-risk coronary plaque. Future studies are needed to establish whether this method can improve the management and treatment of patients with coronary artery disease. FUNDING: Chief Scientist Office Scotland and British Heart Foundation.

Stepwise provisional versus systematic culotte for stenting of true coronary bifurcation lesions: five-year follow-up of the multicentre randomised EBC TWO Trial.

BACKGROUND: The multicentre European Bifurcation Club Trial (EBC TWO) showed no significant differences in 12-month clinical outcomes between patients randomised to a provisional stenting strategy or systematic culotte stenting in non-left main true bifurcations. AIMS: This study aimed to investigate the 5-year clinical results of the EBC TWO Trial. METHODS: A total of 200 patients undergoing stent implantation for non-left main bifurcation lesions were recruited into EBC TWO. Inclusion criteria required a side branch diameter ≥2.5 mm and side branch lesion length >5 mm. Five-year follow-up was completed for 197 patients. The primary endpoint was the composite of all-cause mortality, myocardial infarction, or target vessel revascularisation. RESULTS: The mean side branch stent diameter was 2.7±0.3 mm and mean side branch lesion length was 10.3±7.2 mm. At 5-year follow-up, the primary endpoint occurred in 18.4% of provisional and 23.7% of systematic culotte patients (hazard ratio [HR] 0.75, 95% confidence interval [CI]: 0.41-1.38). No significant differences were identified individually for all-cause mortality (7.8% vs 7.2%, HR 1.11, 95% CI: 0.40-3.05), myocardial infarction (8.7% vs 13.4%, HR 0.64, 95% CI: 0.27-1.50) or target vessel revascularisation (6.8% vs 9.3%, HR 1.12, 95% CI: 0.37-3.34). Stent thrombosis rates were also similar (1.9% vs 3.1%, HR 0.63, 95% CI: 0.11-3.75). There was no significant interaction between the extent of side branch disease and the primary outcome (p=0.34). CONCLUSIONS: In large non-left main true bifurcation lesions, the use of a systematic culotte strategy showed no benefit over provisional stenting for the composite outcome of all-cause mortality, myocardial infarction, or target vessel revascularisation at 5 years. The stepwise provisional approach may be considered preferable for the majority of true coronary bifurcation lesions. CLINICALTRIALS: gov: NCT01560455.

Percutaneous balloon venoplasty of pacemaker-associated superior vena cava obstruction to facilitate upgrade to a biventricular pacing system.

Superior vena cava (SVC) obstruction is an uncommon, but serious, complication of transvenous device implantation. We present a case of a 52-year-old lady admitted for upgrade to a biventricular pacemaker with significant SVC stenosis. Percutaneous balloon venoplasty of the SVC followed by insertion of biventricular pacing leads was carried out as a single procedure with no complications.

The role of antiplatelet therapy in the secondary prevention of coronary artery disease.

PURPOSE OF REVIEW: In this study, we review the evidence for both long-standing and newer oral antiplatelet agents as secondary prevention in coronary artery disease, and give our opinion on where each agent's treatment role lies. RECENT FINDINGS: Platelets play a pathological role in acute coronary syndromes and are therefore a major therapeutic target. The caveat to this is that their physiological haemostatic role means there must be a careful balance between preventing ischaemia and not promoting bleeding. In addition to accepted oral agents (aspirin and clopidogrel), more potent antiplatelet agents have recently become available (prasugrel and ticagrelor) at a cost of increased bleeding. SUMMARY: There is now a choice of three antiplatelet agents to be used in conjunction with aspirin for secondary prevention with dual antiplatelet therapy. Clinicians must now 'tailor' the correct therapy for each patient, depending on their presentation, clinical features and stage of risk.

Percutaneous Repair of Ventricular Ruptures.

Acquired ventricular wall ruptures can be life-threatening. Depending on the pathological features and anatomy, surgical repair can be technically challenging and may be associated with high morbidity and mortality. We present 3 successful percutaneous repairs of different ruptures that used a variety of techniques. (Level of Difficulty: Advanced.).

The EBC TWO Study (European Bifurcation Coronary TWO): A Randomized Comparison of Provisional T-Stenting Versus a Systematic 2 Stent Culotte Strategy in Large Caliber True Bifurcations.

BACKGROUND: For the treatment of coronary bifurcation lesions, a provisional strategy is superior to systematic 2-stent techniques for the most bifurcation lesions. However, complex anatomies with large side branches (SBs) with significant ostial disease length are considered by expert consensus to warrant a 2-stent technique upfront. This consensus view has not been scientifically assessed. METHODS AND RESULTS: Symptomatic patients with large caliber true bifurcation lesions (SB diameter ≥2.5 mm) and significant ostial disease length (≥5 mm) were randomized to either a provisional T-stent strategy or a dual stent culotte technique. Two hundred patients aged 64±10 years, 82% male, were randomized in 20 European centers. The clinical presentations were stable coronary disease (69%) and acute coronary syndromes (31%). SB stent diameter (2.67±0.27 mm) and length (20.30±5.89 mm) confirmed the extent of SB disease. Procedural success (provisional 97%, culotte 94%) and kissing balloon inflation (provisional 95%, culotte 98%) were high. Sixteen percent of patients in the provisional group underwent T-stenting. The primary end point (a composite of death, myocardial infarction, and target vessel revascularization at 12 months) occurred in 7.7% of the provisional T-stent group versus 10.3% of the culotte group (hazard ratio, 1.02; 95% confidence interval, 0.78-1.34; P=0.53). Procedure time, x-ray dose, and cost all favored the simpler procedure. CONCLUSIONS: When treating complex coronary bifurcation lesions with large stenosed SBs, there is no difference between a provisional T-stent strategy and a systematic 2-stent culotte strategy in a composite end point of death, myocardial infarction, and target vessel revascularization at 12 months. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT 01560455.

Optical coherence tomography versus intravascular ultrasound to evaluate stent implantation in patients with calcific coronary artery disease.

AIMS: Stent underexpansion and malapposition are associated with adverse outcomes following percutaneous coronary intervention, but detection and treatment can be challenging in the presence of extensive coronary artery calcification. Frequency domain optical coherence tomography (FD-OCT) is a novel intravascular imaging technique with greater spatial resolution than intravascular ultrasound (IVUS) but its role in the presence of extensive coronary calcification remains unclear. We sought to determine the utility of FD-OCT compared to IVUS imaging to guide percutaneous coronary intervention in patients with severe calcific coronary artery disease. METHODS: 18 matched IVUS and FD-OCT examinations were evaluated following coronary stent implantation in 12 patients (10 male; mean age 70±7 years) undergoing rotational atherectomy for symptomatic calcific coronary artery disease. RESULTS: In-stent luminal areas were smaller (minimum in-stent area 6.77±2.18 vs 7.19±2.62 mm(2), p<0.05), while reference lumen dimensions were similar with FD-OCT compared with IVUS. Stent malapposition was detected in all patients by FD-OCT and in 10 patients by IVUS. The extent of stent malapposition detected was greater (20% vs 6%, p<0.001) with FD-OCT compared to IVUS. Postdilation increased the in-stent luminal area (minimum in-stent area: 8.15±1.90 vs 7.30±1.62 mm(2), p<0.05) and reduced the extent of stent malapposition (19% vs 34%, p<0.005) when assessed by FD-OCT, but not IVUS. CONCLUSIONS: Acute stent malapposition occurs frequently in patients with calcific coronary disease undergoing rotational atherectomy and stent implantation. In the presence of extensive coronary artery calcification, FD-OCT affords enhanced stent visualisation and detection of malapposition, facilitating improved postdilation stent apposition and minimal luminal areas. TRIAL REGISTRATION NUMBER: NCT02065102.

Prospective peer review of regional percutaneous interventional procedures: a tool for quality control and revalidation.

AIMS: Current quality measures of percutaneous coronary intervention (PCI) procedures are based on the incidence of major adverse cardiac events (MACE). This crude marker ignores the many clinical nuances that make for sound decision making in PCI. We have established a prospective peer review audit tool to determine the quality of PCI within our cardiac network, which consists of five PCI hospitals serving a population of 1.4 million people in Sussex, UK. METHODS AND RESULTS: Analysis of 10% of all PCI cases selected at random each month by a non-clinical audit manager is made by a rotating panel of two PCI operators and one cardiac surgeon. Each PCI case is assessed for anatomical suitability, lesion severity, strategic appropriateness and final outcome. Panel findings were reported back to the operator and the audit manager. A total of 326 cases were assessed by the review committee. Results were disseminated to individual operators. Coronary anatomy and lesion severity were considered appropriate for PCI in 94.2% and 96.0% of cases, respectively. Appropriateness of strategy was confirmed in 86.2% and the outcome considered satisfactory in 90.8%. A total of 242 subsequent cases were analysed to assess practice trends. This analysis demonstrated a statistically significant improvement in clinical decision making with respect to appropriateness of strategy (from 86.2% to 92.6%; p=0.004). CONCLUSIONS: Prospective peer review of percutaneous coronary intervention cases by a rotating regional committee is valuable in ensuring procedural quality.

Simple or complex stenting for bifurcation coronary lesions: a patient-level pooled-analysis of the Nordic Bifurcation Study and the British Bifurcation Coronary Study.

BACKGROUND: Controversy persists regarding the correct strategy for bifurcation lesions. Therefore, we combined the patient-level data from 2 large trials with similar methodology: the NORDIC Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study (BBC ONE). METHODS AND RESULTS: Both randomized trials compared simple (provisional T-stenting) versus complex techniques, using drug-eluting stents. In the simple group (n=457), 129 patients had final kissing balloon dilatation in addition to main vessel stenting, and 16 had T-stenting. In the complex group (n=456), 272 underwent crush, 118 culotte, and 59 T-stenting techniques. A composite end point at 9 months of all-cause death, myocardial infarction, and target vessel revascularization occurred in 10.1% of the simple versus 17.3% of the complex group (hazard ratio 1.84 [95% confidence interval 1.28 to 2.66], P=0.001). Procedure duration, contrast, and x-ray dose favored the simple approach. Subgroup analysis revealed similar composite end point results for true bifurcations (n=657, simple 9.2% versus complex 17.3%; hazard ratio 1.90 [95% confidence interval 1.22 to 2.94], P=0.004), wide-angled bifurcations >60 to 70° (n=217, simple 9.6% versus complex 15.7%; hazard ratio 1.67 [ 95% confidence interval 0.78 to 3.62], P=0.186), large (≥2.75 mm) diameter side branches (n=281, simple 10.4% versus complex 20.7%; hazard ratio 2.42 [ 95% confidence interval 1.22 to 4.80], P=0.011), longer length (>5 mm) ostial side branch lesions (n=464, simple 12.1% versus complex 19.1%; hazard ratio 1.71 [95% confidence interval 1.05 to 2.77], P=0.029), or equivalent sized vessels (side branch <0.25 mm smaller than main vessel) (n=108, simple 12.0% versus complex 15.5%; hazard ratio 1.35 [95% confidence interval 0.48 to 3.70], P=0.57). CONCLUSIONS: For bifurcation lesions, a provisional single-stent approach is superior to systematic dual stenting techniques in terms of safety and efficacy. A complex approach does not appear to be beneficial in more anatomically complicated lesions.

Device therapy for the management of cardiac tachyarrhythmias.

Implantation of devices that can terminate cardiac arrhythmias has increased rapidly over recent years. This article looks at the evidence base for using such devices in the primary and secondary prevention of sudden arrhythmic death, discusses who should have a device and examines the issues surrounding implantation. Recent advances in technology and the future direction of therapy are also reviewed.

Inhibitory effects of P2Y12 receptor antagonists on TRAP-induced platelet aggregation, procoagulant activity, microparticle formation and intracellular calcium responses in patients with acute coronary syndromes.

Thrombin induces platelet aggregation and membrane rearrangements leading to enhanced procoagulant activity and microparticle production, all of which are thought to contribute to thrombus formation in patients with acute coronary syndromes (ACS). Clopidogrel, an adenosine diphosphate (ADP) receptor antagonist acting at the P2Y(12) receptor, has been shown to provide clinical benefit in ACS. We aimed to investigate the effects of clopidogrel ex vivo and another ADP-antagonist, AR-C69931MX in vitro on thrombin receptor activating peptide (TRAP)-induced platelet aggregation, procoagulant activity, microparticle formation and [Ca(2+)]i responses in patients with ACS. Measurements were performed in platelet-rich plasma using aggregometry and flow cytometry (n = 12). Clopidogrel (300 mg loading dose plus 75 mg daily) significantly inhibited TRAP-induced aggregation, procoagulant activity (annexin V binding) and microparticle production (all P < 0.05) but not as extensively as AR-C69931MX (400 nmol/l). [Ca(2+)]i responses induced by a combination of TRAP and ADP designed to mimic the physiological effects of released ADP showed that clopidogrel partially and AR-C69931MX completely removed the ADP component of the [Ca(2+)]i responses (n = 6). The results provide new information on the mechanisms involved in the beneficial effects of P2Y(12) antagonists in patients with ACS.

Leukocyte count and leukocyte ecto-nucleotidase are major determinants of the effects of adenosine triphosphate and adenosine diphosphate on platelet aggregation in human blood.

ADP induces platelet aggregation in human whole blood and platelet-rich plasma (PRP). ATP induces aggregation in whole blood only; this involves leukocytes and is mediated by ADP. Here we studied ATP- and ADP-induced aggregation in patients with raised leukocyte counts (mean 46.2x10(3) leukocytes/microl). Platelet aggregation was measured by platelet counting. ATP, ADP and metabolites were measured by HPLC. Aggregation to ADP (1-10 microM) and ATP (10-100 microM) was markedly reduced, but to ATP (1000 microM) was enhanced (all p<0.001). Aggregation to ADP in PRP was normal. Increasing the leukocyte count in normal blood reproduced the findings in the patients. Adding leukocytes (either MNLs or PMNLs) to normal PRP enabled a response to ATP and caused marked inhibition of ADP-induced aggregation. Breakdown of ATP or ADP to AMP and adenosine in leukocyte-rich plasma was rapid (t1/2=4 min) and far higher than in cell-free plasma or PRP. With ATP there was also formation of ADP, maximal at 4 min. The presence of the ectonucleotidase NTPDase1 (CD39) was demonstrated on MNLs (all of the monocytes and a proportion of the lymphocytes) and all PMNLs by flow cytometry. We conclude that leukocytes provide a means of dephosphorylating ATP which enables ATP-induced aggregation via conversion to ADP, but also convert ADP to AMP and adenosine. Platelet aggregation extent is a balance between these activities, and high white cell counts influence this balance.