Stroke in mitral valve prolapse: risk factors and left atrial function in cryptogenic versus non-cryptogenic ischemic subtypes.

Background and purpose: Mitral valve prolapse (MVP) has been associated with an increased risk of ischemic stroke. Older age, thicker mitral leaflets, and significant mitral regurgitation (MR) leading to atrial fibrillation have been traditionally considered risk factors for ischemic stroke in MVP. However, specific risk factors for MVP-stroke subtypes are not well defined. The aim of this study is to evaluate clinical and echocardiographic parameters, including left atrial (LA) function, in MVP with cryptogenic (C) vs. non-cryptogenic (NC) stroke. Methods: In this case-control matched study, MVPs were identified in consecutive echocardiograms obtained after a stroke from January 2013 to December2016 at the University of California, San Francisco. MVP was defined as leaflet displacement ≥2 mm in the parasternal long-axis view at end-systole. Age/gender matched MVPs without stroke and healthy controls without MVP were also identified. We analyzed LA end-systolic/diastolic volume index, emptying fraction (LAEF), function index (LAFI), and global longitudinal strain in all MVPs and controls. We also measured left ventricular (LV) volume indexes, mass index, ejection fraction (EF), degree of MR and leaflet thickness. Results: We identified a total of 30 MVPs (age 70 ± 12, 50% females) with stroke (11 with C- and 19 with NC-stroke), 20 age/gender matched MVPs without a stroke and 16 controls. MVPs without stroke had lower BMI, less hypertension but more MR (≥moderate in 45% vs. 17%), more abnormal LA function (lower LAEF, LAFI) and larger LV volumes/mass (all p < 0.05) when compared to MVPs with stroke. Leaflet thickness was overall mild (<3 mm) and similar in the 2 groups. Within the MVP stroke group, NC-stroke had higher BMI, more hypertension and more atrial fibrillation compared to C-stroke. In the variables tested, patients with C-stroke did not differ from controls. Conclusions: MVP-related MR may be protective against stroke despite abnormal LA function. Risk of NC-stroke in MVP is related to common stroke risk factors rather than mitral valve leaflet thickness. The etiology of C-stroke in MVP warrants further studies.

Mitral annular calcification as a predictor of stroke in the multiethnic study of atherosclerosis.

BACKGROUND: Mitral annular calcification (MAC) is associated with an increased risk for cardiovascular morbidity and mortality. This study provides recent data on the association between cardiac computed tomography (CT) derived MAC and 15 years of stroke risk in a racially diverse cohort. METHODS: All multiethnic studies of atherosclerosis participants ( n  = 6814) who completed a cardiac CT at baseline were included in this analysis. MAC score was calculated from cardiac CT using the Agatston and volume score methods. Multivariable Cox proportional hazard regression models were used to compute hazard ratios for the association between MAC and stroke after adjusting for traditional cardiovascular risk factors, inflammatory markers, coronary artery calcium score, atrial fibrillation, and left atrial size. RESULTS: Overall, 9% of participants (644/6814) had MAC at baseline. Over a surveillance period of 15 years, 304 strokes occurred, and 79% were ischemic strokes. After adjusting for age, sex, race/ethnicity, SBP, diabetes, smoking, fibrinogen, IL-6, high-sensitivity C-reactive protein, and coronary artery calcium score, baseline MAC was associated with increased risk for all strokes [hazard ratio 1.68; 95% confidence interval (CI) 1.22-2.30: P  = 0.0013]. When atrial fibrillation/flutter and left atrial size were included in the final multivariable model, MAC remained a predictor of all strokes (hazard ratio 1.93; 95% CI 1.22-3.05: P  < 0.0051) and ischemic stroke (hazard ratio 2.03; 95% CI 1.24-3.31: P  < 0.0046). CONCLUSION: MAC is an independent predictor of long-term stroke risk in a racially diverse population beyond conventional cardiovascular risk factors and atrial fibrillation.

Obstructive coronary artery disease in symptomatic diabetics with zero coronary calcium score: are we missing something?

BACKGROUND: Prevalence and severity of coronary artery disease (CAD) in symptomatic patients with zero coronary artery calcium score (CACS) are unclear, particularly in regard to the diabetic population, which represents, per se, a subgroup at increased cardiovascular risk. The aim of this study was to investigate the prevalence and severity of CAD by coronary computed tomography angiography (CCTA) in a symptomatic diabetic cohort with zero CACS. METHODS: All consecutive symptomatic diabetics referred for CAD suspicion were included in this study. All subjects underwent a noncontrast coronary artery calcium scan followed by CCTA. CACS was quantified using the Agatston method. CAD was defined as a total plaque score (TPS) greater than zero. Obstructive and severe obstructive CAD were defined respectively as luminal stenosis >50% and >70% in at least one coronary segment. RESULTS: We identified 1722 symptomatic diabetics (mean age 62.5 ± 12.9 years, 62% men). One hundred and eleven subjects had zero CACS and TPS >0 (mean age was 49.5 ± 14.8, 58% women, 56% Hispanics). Sixty-five patients (58.5%) had one-vessel disease, followed by 30 (27%) with two-vessel disease and 14 (12.6%) with ≥ three-vessel disease. Obstructive CAD was found in 11 subjects and, among these, three were categorized as severe obstructive CAD. CONCLUSION: In symptomatic diabetic patients with zero CACS, CAD, including obstructive disease, can still occur and is predominant in middle-aged adults, women and Hispanics. In symptomatic diabetics CCTA is a critical step for accurate risk stratification even when CACS would have placed some of these individuals in a lower-risk category.

Coronary computed tomography angiography evaluation of plaque morphology and its relationship to HDL and total cholesterol to HDL ratio.

BACKGROUND: While population studies have demonstrated that high density lipoprotein cholesterol (HDL-C) and the ratio of total cholesterol to HDL (TC/HDL) improve cardiovascular risk prediction, the mechanism by which these parameters protect the cardiovascular system remains uncertain. OBJECTIVE: To investigate the relationship between the HDL-C level and the total cholesterol to HDL (TC/HDL) ratio with the morphology of coronary artery plaque as determined by coronary computed tomography angiography (CCTA). METHODS: This is a cross-sectional study involving 190 subjects with stable coronary artery disease. Semi-automated plaque analysis software was utilized to quantify plaque and plaque volumes are presented as total atheroma volume normalized (TAVnorm). Multivariate regression models were used to evaluate the association of HDL-C and TC/HDL ratio with coronary plaque volumes. RESULTS: Of the 190 subjects the average (SD) age was 58.9 (9.8) years, with 63% being male. After adjustment for cardiovascular risk factors, HDL- C (>40 mg/dl) is inversely associated with fibrous (p = 0.003), fibrous fatty (p = 0.007), low attenuation plaque (LAP) (p = 0.007), total non-calcified plaque (TNCP) (p = 0.002) and total plaque (TP)(p = 0.004) volume. Furthermore, the TC/HDL ratio (> 4.0) is associated with fibrous (p = 0.047) and total non-calcified plaque (p = 0.039), but not with fibrofatty, LAP, dense calcified plaque, or TP volume. CONCLUSION: There is a strong association between low HDL-C levels and increasing TC/HDL ratio with certain types of coronary plaque characteristics, independent of traditional risk factors. The findings of this study suggest mechanistic evidence supporting the protective role of HDL-C and the TC/HDL ratio's clinical relevance in coronary artery disease management.

Arterial stiffness and left ventricular structure assessed by cardiac computed tomography in a multiethnic population.

BACKGROUND: Arterial stiffness expressed by cardio-ankle vascular index (CAVI) is a marker of arteriosclerosis. It can increase vascular load, which in turn may affect the viscoelastic myocardial properties and the left ventricular compliance. In the present study, we sought to investigate the association between CAVI and left ventricular structure assessed by cardiac computed tomography (CT) in a multiethnic adult cohort. METHODS: CAVI was measured using the vascular screening system VaSera VS-1500 AU (Fukuda Denshi, Japan). The average of right and left CAVI values was utilized for the analysis. Left ventricular mass and volume were computed on mid-diastolic cardiac CTA images and indexed to body surface area (BSA) to obtain left ventricular mass index (LVMI) and left ventricular volume index (LVVI). The association between CAVI, LVMI and LVVI was assessed by multiple linear regression analysis. RESULTS: The study cohort was composed of 255 individuals (mean age 56.2 ±â€Š13.4, 66% men). An abnormal CAVI value was defined as at least 8. One hundred and seventy-one individuals had CAVI values at least 8: they were older (P < 0.0001), more affected by of hypertension (P < 0.0001), dyslipidaemia (P = 0.0002), diabetes mellitus (P < 0.0001), previous history of myocardial infarction (P = 0.0246) or angioplasty (P = 0.0143), had higher CAC score (P < 0.0001) and prevalence of obstructive coronary artery disease (P = 0.001). When analysing CT-derived left ventricular geometry parameters, we found that individuals with abnormal CAVI had significantly smaller LVVI (P < 0.0001). This association remained valid after adjustments for age, sex, ethnicity (P = 0.0002), hypertension, dyslipidaemia, CAC score (P = 0.0004) and diabetes mellitus (P = 0.0034). The association between abnormal CAVI and LVMI was not significant in the unadjusted model (P = 0.593). CONCLUSION: Reduced vascular distensibility in an adult multiethnic population is associated with smaller LVVI beyond traditional cardiovascular risk factors suggesting that impaired left ventricular compliance mainly parallels increased arterial stiffness.

Diagnostic algorithm for HFpEF: how much is the recent consensus applicable in clinical practice?

Heart failure with preserved ejection fraction (HFpEF) represents an important cardiovascular entity with increasing prevalence and relatively high mortality. The agreement about diagnostic algorithm for HFpEF is still missing. Echocardiographic approach remains the cornerstone in HFpEF diagnosis. Echocardiographic diastolic stress test provides numerous useful parameters that correlated well with indexes obtained by cardiac catheterization. Recently published consensus recommended new scoring system that included functional and structural echocardiographic parameters, as well as biomarkers. The new score for evaluation of HFpEF introduces a new set of parameters and proposed novel cutoff values for some of them. There are several important points that need to be resolved before full acceptance and clinical usage. First, some cutoff values are new and represent the result of expert consensus, without previous validation. Second, many patients with hypertension, obesity, and diabetes would be referred for further investigations as the result of this scoring, which is difficult to achieve in clinical circumstances. Third, the consensus equalized non-invasive and invasive diastolic stress tests in diagnosing of HFpEF, which is not a small issue. Namely, even though cardiac catheterization provides the final confirmation of elevated left ventricular filling pressures, it is still an invasive method, associated with procedural risk and other limitations. The aim of this review was to summarize the current knowledge diagnosis of HFpEF, as well as the recent consensus about diagnostic algorithm in patients with suspected HFpEF with its advantages and disadvantages.

Diabetic cardiomyopathy: How can cardiac magnetic resonance help?

Diabetes cardiomyopathy is a specific form of cardiac disease characteristic for diabetic patients. Development of echocardiography enabled diagnosis of diabetic cardiomyopathy significantly before the occurrence of heart failure. Previously was believed that left ventricular (LV) diastolic dysfunction represents the first detectable stage of diabetic cardiomyopathy. However, speckle tracking imaging and strain evaluation showed that mechanical changes occur before LV diastolic dysfunction. Nevertheless, it seems that the first detectable stage of diabetic cardiomyopathy is myocardial interstitial fibrosis, which currently could be diagnosed predominantly by cardiac magnetic resonance. T1 mapping evaluation before and after contrast injection enables assessment of extracellular volume (ECV) and provides qualitative and quantitative assessment of interstitial myocardial fibrosis in diabetic patients. Studies showed a strong correlation between ECV-parameter of interstitial fibrosis and level of glycated hemoglobin-main parameter of glucose control in diabetes. This stage of fibrosis is still not LV hypertrophy and it is reversible, which is of a great importance because of timely initiation of treatment. The necessity for early diagnose is significantly increasing due to the fact that diabetes and arterial hypertension are concomitant disorders in the large number of diabetic patients and it has been known that the risk of interstitial myocardial fibrosis is multiplied in patients with both conditions. Future follow-up investigations are essential to determine the causal relationship between interstitial fibrosis and outcome in these patients. The aim of this review was to summarize the current knowledge and clinical usefulness of CMR in diabetic patients.

Balloon aortic valvuloplasty before noncardiac surgery in severe aortic stenosis: a single-center experience.

OBJECTIVES: The aim of this study is to investigate the role and short-term results of balloon aortic valvuloplasty (BAV) before noncardiac surgery in a high selected cohort of patients. BACKGROUND: Aortic stenosis is one of the most common valvular heart diseases and a well recognized risk factor for perioperative mortality. METHODS: Between May 2012 and July 2013 we enrolled 15 consecutive patients with severe aortic stenosis to allow urgent major noncardiac surgery. They had been excluded from surgical aortic valve replacement and transcatheter aortic valve implantation. RESULTS: Fifteen patients underwent BAV as a bridge to noncardiac surgery. They were elderly (mean age 81 ±â€Š5 years) and predominantly men (66%) with high surgery risk (mean logistic EuroSCORE: 31.1 ±â€Š18.2%). Three patients underwent vascular surgery, five underwent thoracic surgery, five were subjected to major abdominal surgery and in the last two patients orthopedic surgery and mastectomy were performed. No adverse events were observed in the perioperative period. Six patients (40%) were in New York Heart Association class III or IV. Mean aortic valve area was 0.52 ±â€Š0.1 cm/m; mean aortic pressure gradient was 55.6 ±â€Š10.8 mmHg. BAV was performed successfully in all patients. The mean peak-to-peak gradient assessed by catheterization significantly reduced after BAV (from 69.0 ±â€Š22.1 to 29.7 ±â€Š9.3 mmHg; P < 0.0001). The echocardiographic mean gradient was also significantly improved (from 55.6 ±â€Š10.8 to 33.8 ±â€Š7.9 mmHg; P < 0.0001). Survival at 30 days and at 6 months' follow-up respectively was 100%. At 6 months' follow-up clinical status according to New York Heart Association class was significantly improved (P < 0.0001). CONCLUSION: BAV is well tolerated and effective in high-risk patients with severe aortic stenosis undergoing noncardiac surgery with good short-term survival. It could represent a valid choice of treatment prior to noncardiac surgery in these high-risk patients.

The clinical impact of contemporary stress echocardiography in morbid obesity for the assessment of coronary artery disease.

OBJECTIVE: Non-invasive cardiac imaging may suffer from poor image quality in morbidly obese individuals. This study aimed to determine the clinical value of contemporary stress echocardiography (SE) in morbidly obese patients referred for assessment of suspected coronary artery disease (CAD). METHODS: This prospective, multicentre observational study was conducted in two district hospitals and one tertiary centre in London, UK. Individuals with body mass index ≥35 kg/m(2) referred for SE were evaluated. The percentage of patients with obstructive CAD on coronary angiography, following abnormal SE, was assessed. Patient outcomes were determined with follow-up for the composite end-point of all-cause mortality, myocardial infarction and late revascularisation. RESULTS: Over a 13-month period, 209 morbidly obese patients underwent SE, and contrast agent was used in 96% of patients. A diagnostic result was obtained in 200/209 (96%) patients. Of 32 (15%) patients with inducible ischaemia, 25 underwent angiography, 22 (88%) had corresponding significant CAD and, of these, 16 (77%) underwent revascularisation. Conversely, only 2/157 patients (1.3%) with normal SE underwent angiography, and none underwent revascularisation. Over a mean follow-up period of 17.8±5.4 months, there were nine events. The annualised cardiac event rate after a normal SE was 0.95%. Events were more frequent in patients with inducible ischaemia versus those without ischaemia (5/32 (15.6%) vs 4/153 (2.6%); p=0.002). Ejection fraction <50% (HR 9.5; 95% CI 2.4 to 38.0; p=0.002) and inducible ischaemia (HR 9.4; 95% CI 2.5 to 35.8; p=0.001) were predictors of outcome on univariable Cox regression analysis. CONCLUSIONS: Contemporary SE has excellent feasibility and positive predictive value and resulted in appropriate risk stratification of symptomatic patients with significant obesity. A normal SE portends an excellent outcome over the short-intermediate term in this high-risk patient population.