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Objective: Treated HIV infection is associated with a higher incidence of coronary artery disease and myocardial infarction, although the mechanisms remain unclear. We sought to characterise the burden of coronary artery disease in men with HIV using retrospective data from invasive coronary angiograms in patients presenting with acute coronary syndrome (ACS)., Methods: Demographic and coronary angiographic data were obtained from 160 men with ST elevation myocardial infarction, non-STEMI or high-risk chest pain; 73 HIV-infected cases and 87 age-matched controls. The burden of coronary disease was calculated using the Gensini Angiographic Scoring System by 2 independent cardiologists blinded to HIV status., Results: The 2 groups were matched for age, sex and cardiac event subtype and there was no difference in rates of smoking or cholesterol levels. Compared with control participants, patients with HIV had higher usage of antihypertensives (46 (63%) vs 30 (35%), p<0.001) and statins (47 (64%) vs 29 (33%), p<0.001). There was no difference in plaque distribution between both groups; however, the Gensini score was 42% lower in cases with HIV than in controls (p<0.03). C reactive protein was higher in cases with HIV (13.4±15.4 vs 3.7±3.6)., Conclusions: Men with HIV presenting with ACS paradoxically had a lower burden of coronary plaque than matched controls, despite more aggressive risk factor management, suggesting that plaque vulnerability, rather than total burden of atherosclerosis, may be important in the pathophysiology of coronary artery disease in men with HIV., Competing Interests: Conflicts of Interest: None declared.

Renal denervation has been shown to be safe and effective in reducing blood pressure in treatment-resistant hypertensive patients. We describe a 65-year-old lady with essential hypertension who underwent renal denervation using the Vessix™ single shot multielectrode system. Twelve months later renal duplex scanning documented increased velocities in the left renal artery and repeat angiography confirmed the development of a new stenosis. Although renal denervation is a promising therapy, we advise caution as large randomized blinded studies with long-term follow-up are still ongoing., (© 2014 Wiley Periodicals, Inc.)

Mitral regurgitation is the most common valve abnormality worldwide and its prevalence is expected to increase in the future due to aging of the population. Percutaneous mitral valve repair therapies may offer an opportunity to treat severe MR in the elderly or other high-risk groups who would otherwise be ineligible for surgery. The MitraClip system uses edge-to-edge coaptation of the mitral leaflets to create a double-orifice valve and reduce MR. It has been performed in over 10 000 patients to date, and as experience has improved, procedural times have shortened from over 200 minutes to less than 100 minutes, with increasing numbers of patients being left with ≤ grade 2+ MR. This review will focus on the literature available on MitraClip and other novel percutaneous techniques that are being developed for the treatment of severe MR., (Copyright © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Despite improvements in medical therapy, the overall prognosis of patients with severe pulmonary arterial hypertension remains poor. Heart-lung transplantation or bilateral lung transplantation is the final pathway for a minority. This paper describes both established and novel percutaneous interventional techniques that may palliate or bridge pulmonary hypertension patients to transplantation., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Revascularization strategies for multivessel coronary artery disease include percutaneous coronary intervention and coronary artery bypass grafting. In this study, we compared the completeness of revascularization as assessed by coronary angiography and by quantitative serial perfusion imaging using cardiovascular magnetic resonance., Methods and Results: Patients with multivessel coronary disease were recruited into a randomized trial of treatment with either coronary artery bypass grafting or percutaneous coronary intervention. Angiographic disease burden was determined by the Bypass Angioplasty Revascularization Investigation (BARI) myocardial jeopardy index. Cardiovascular magnetic resonance first-pass perfusion imaging was performed before and 5 to 6 months after revascularization. Using model-independent deconvolution, hyperemic myocardial blood flow was evaluated, and ischemic burden was quantified. Sixty-seven patients completed follow-up (33 coronary artery bypass grafting and 34 percutaneous coronary intervention). The myocardial jeopardy index was 80.7±15.2% at baseline and 6.9±11.3% after revascularization (P<0.0001), with revascularization deemed complete in 62.7% of patients. Relative to cardiovascular magnetic resonance, angiographic assessment overestimated disease burden at baseline (80.7±15.2% versus 49.9±29.2% [P<0.0001]), but underestimated it postprocedure (6.9±11.3% versus 28.1±33.4% [P<0.0001]). Fewer patients achieved complete revascularization based on functional criteria than on angiographic assessment (38.8% versus 62.7%; P=0.015). After revascularization, hyperemic myocardial blood flow was significantly higher in segments supplied by arterial bypass grafts than those supplied by venous grafts (2.04±0.82 mL/min per gram versus 1.89±0.81 mL/min per gram, respectively; P=0.04)., Conclusions: Angiographic assessment may overestimate disease burden before revascularization, and underestimate residual ischemia after revascularization. Functional data demonstrate that a significant burden of ischemia remains even after angiographically defined successful revascularization.

We present a case of a 76-year-old man with ischemic cardiomyopathy. Cardiac magnetic resonance imaging demonstrated severe left ventricular (LV) impairment with possibility of scar formation. Cardiac resynchronization therapy was employed with the aid of a novel quadripolar LV lead. The quadripolar LV lead can be programmed for 10 different pacing configurations, allowing the electrophysiologist freedom to optimize the vector around scar and also avoid phrenic nerve stimulation without the requirement of LV lead repositioning., (©2011, The Authors. Journal compilation ©2011 Wiley Periodicals, Inc.)

Objectives: The purpose of this study was to assess the diagnostic accuracy of blood oxygen-level dependent (BOLD) MRI in suspected coronary artery disease (CAD)., Background: By exploiting the paramagnetic properties of deoxyhemoglobin, BOLD magnetic resonance imaging can detect myocardial ischemia. We applied BOLD imaging and first-pass perfusion techniques to: 1) examine the pathophysiological relationship between coronary stenosis, perfusion, ventricular scar, and myocardial oxygenation; and 2) evaluate the diagnostic performance of BOLD imaging in the clinical setting., Methods: BOLD and first-pass perfusion images were acquired at rest and stress (4 to 5 min intravenous adenosine, 140 μg/kg/min) and assessed quantitatively (using a BOLD signal intensity index [stress/resting signal intensity], and absolute quantification of perfusion by model-independent deconvolution). A BOLD signal intensity index threshold to identify ischemic myocardium was first determined in a derivation arm (25 CAD patients and 20 healthy volunteers). To determine diagnostic performance, this was then applied in a separate group comprising 60 patients with suspected CAD referred for diagnostic angiography., Results: Prospective evaluation of BOLD imaging yielded an accuracy of 84%, a sensitivity of 92%, and a specificity of 72% for detecting myocardial ischemia and 86%, 92%, and 72%, respectively, for identifying significant coronary stenosis. Segment-based analysis revealed evidence of dissociation between oxygenation and perfusion (r = -0.26), with a weaker correlation of quantitative coronary angiography with myocardial oxygenation (r = -0.20) than with perfusion (r = -0.40; p = 0.005 for difference). Hypertension increased the odds of an abnormal BOLD response, but diabetes mellitus, hypercholesterolemia, and the presence of ventricular scar were not associated with significant deoxygenation., Conclusions: BOLD imaging provides valuable insights into the pathophysiology of CAD; myocardial hypoperfusion is not necessarily commensurate with deoxygenation. In the clinical setting, BOLD imaging achieves favorable accuracy for identifying the anatomic and functional significance of CAD., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Absolute quantification of perfusion with cardiovascular magnetic resonance has not previously been applied in patients with coronary artery bypass grafting (CABG). Owing to increased contrast bolus dispersion due to the greater distance of travel through a bypass graft, this approach may result in systematic underestimation of myocardial blood flow (MBF). As resting MBF remains normal in segments supplied by noncritical coronary stenosis (<85%), measurement of perfusion in such territories may be utilized to reveal systematic error in the quantification of MBF. The objective of this study was to test whether absolute quantification of perfusion with cardiovascular magnetic resonance systematically underestimates MBF in segments subtended by bypass grafts., Methods and Results: The study population comprised 28 patients undergoing elective CABG for treatment of multivessel coronary artery disease. Eligible patients had angiographic evidence of at least 1 myocardial segment subtended by a noncritically stenosed coronary artery (<85%). Subjects were studied at 1.5 T, with evaluation of resting MBF using model-independent deconvolution. Analyses were confined to myocardial segments subtended by native coronary arteries with <85% stenosis at baseline, and MBF was compared in grafted and ungrafted segments before and after revascularization. A total of 249 segments were subtended by coronary arteries with <85% stenosis at baseline. After revascularization, there was no significant difference in MBF in ungrafted (0.82±0.19 mL/min/g) versus grafted segments (0.82±0.15 mL/min/g, P=0.57). In the latter, MBF after revascularization did not change significantly from baseline (0.86±0.20 mL/min/g, P=0.82)., Conclusions: Model-independent deconvolution analysis does not systematically underestimate blood flow in graft-subtended territories, justifying the use of this methodology to evaluate myocardial perfusion in patients with CABG.

Background: It is recognized that the interplay between myocardial ischemia, perfusion, and oxygenation in the setting of coronary artery disease (CAD) is complex and that myocardial oxygenation and perfusion may become dissociated. Blood oxygen level-dependent (BOLD) cardiovascular magnetic resonance (CMR) has the potential to noninvasively measure myocardial oxygenation, whereas positron emission tomography (PET) with oxygen-15 labeled water is the gold standard technique for myocardial blood flow quantification. Thus, we sought to apply BOLD CMR at 3 T and oxygen-15-labeled water PET in patients with CAD and normal volunteers to better understand the relationship between regional myocardial oxygenation and blood flow during vasodilator stress., Methods and Results: Twenty-two patients (age, 62+/-8 years; 16 men) with CAD (at least 1 stenosis > or =50% on quantitative coronary angiography) and 10 normal volunteers (age, 58+/-6 years; 6 men) underwent 3-T BOLD CMR and PET. For BOLD CMR, 4 to 6 midventricular short-axis images were acquired at rest and during adenosine stress (140 microg/kg/min). Using PET with oxygen-15-labeled water, myocardial blood flow was measured at baseline and during adenosine in the same slices. BOLD images were divided into 6 segments, and mean signal intensities calculated. Taking > or =50% stenosis on quantitative coronary angiography as the gold standard, cutoff values for stress myocardial blood flow (<2.45 mL/min/g; AUC, 0.83) and BOLD signal intensity change (<3.74%; AUC, 0.78) were determined to define ischemic segments. BOLD CMR and PET agreed on the presence or absence of ischemia in 18 of the 22 patients (82%) and in all normal subjects. On a per-segment analysis, 40% of myocardial segments with stress myocardial blood flow below the cutoff of 2.45 mL/min/g did not show deoxygenation, whereas 88% of segments with normal perfusion also had normal oxygenation measurements., Conclusions: Regional myocardial perfusion and oxygenation may be dissociated, indicating that in patients with CAD, reduced perfusion does not always lead to deoxygenation.

Cigarette smoking is the leading preventable cause of death worldwide, and a considerable proportion of smoking-related fatalities are attributable to coronary artery disease (CAD). The detrimental effects of smoking span all stages in the development of CAD ranging from the early functional alterations in the endothelium and the microcirculation to the late clinicopathological manifestations of atherosclerotic plaques. Smoking results in the generation of free radicals and increased oxidative stress which plays a central role in the pathogenetic mechanisms leading to atherosclerotic disease. It causes reduced nitric oxide bioavailability and lipid peroxidation which are crucial initial steps of plaque formation. Furthermore, smoking enhances leukocyte and platelet activation and promotes local and systemic inflammation, which contribute to plaque progression and maturation. Finally, alterations in fibrinolytic and prothrombotic factors create a pro-thrombogenic environment which harbours the risk of plaque rupture and thrombosis. In smokers, the cessation of smoking is the most important intervention for cardiovascular risk reduction. Total mortality can be reduced by 36% which is comparable to established modern secondary preventive therapies. Nonetheless, non-aided cessation attempts are notoriously poor with a success rate of less than 10%. Patient counselling and pharmacological therapies are important aides for smoking cessation and can improve success rates by two to threefold. However, there is still need for improved strategies of smoking cessation to reduce the high socioeconomic impact of smoking.

Background: Increased aortic stiffness markers - aortic pulse wave velocity (PWV) and augmentation index (AIx) - are powerful predictors of survival in ESRD patients - well-recognized for the high prevalence of coronary artery disease (CAD) and unusually high PWV and AIx. Recently, decreased aortic compliance has been shown to be predictive of primary coronary events in hypertensive patients with normal renal function. We aimed to explore relationships between arterial stiffness and CAD in cohorts of patients with chronic kidney disease (CKD)., Methods and Results: 46 patients with chronic kidney disease (33 males, aged 55.7+/- 13.2 years, 20 on dialysis, 18 post renal transplantation, and 8 with glomerular filtration rate (GFR) between 10 and 25 ml/min) underwent coronary angiography for the assessment of CAD. PWV and aortic AIx were determined from pulse waveform analysis of arterial waveforms recorded by applanation tonometry using a SphygmoCortm device. The atherosclerosis burden score was calculated by adding the percentage luminal reduction of the most severe lesion in each artery. Patients with normal angiograms had significantly less arterial stiffness (as reflected by both a lower PWV=8.42+/-1.53 m/s and a lower AIx=17.9+/-5.55 %) compared with the 35 subjects with evidence of obstructive coronary disease at angiography (PWV=9.21+/-1.15 m/s and AIx=23.4+/-5.4 %, P<0.05 for both). Moreover, as more coronary vessels were affected, PWV and AIx increased proportionally. Based on receiver operating characteristics (ROC) curve analysis mean PWV levels showed an optimal cut-off point at 8.35 m/s (sensitivity=0.77; specificity=0.60), while mean AIx levels showed an optimal cut-off point at 17% (sensitivity=0.87; specificity=0.70). There was a statistically significant linear relationship between the atherosclerosis burden and both measures of arterial stiffness: PWV (r=0.31, p=0.007) and AIx (r=0.46, p=0.003). Independent predictors for the arterial stiffness parameters in this CKD population (multiple stepwise regression analysis) were age (r=0.69 for PWV and r=0.62 for AIx), and mean arterial pressure (MAP) (for AIx, p<0.0001)., Conclusion: This study provides the first direct evidence in a cross-sectional investigation that PWV and AIx are related to the extent of coronary obstruction in CKD patients.