Contrast Enhancement of the Right Ventricle during Coronary CT Angiography – Is It Necessary?

Purpose

It is unclear if prolonged contrast media injection, to improve right ventricular visualization during coronary CT angiography, leads to increased detection of right ventricle pathology. The purpose of this study was to evaluate right ventricle enhancement and subsequent detection of right ventricle disease during coronary CT angiography.

Materials and Methods

472 consecutive patients referred for screening coronary CT angiography were retrospectively evaluated. Every patient underwent multidetector-row CT of the coronary arteries: 128x 0.6mm coll., 100-120kV, rot. time 0.28s, ref. mAs 350 and received an individualized (P3T) contrast bolus injection of iodinated contrast medium (300 mgI/ml). Patient data were analyzed to assess right ventricle enhancement (HU) and right ventricle pathology. Image quality was defined good when right ventricle enhancement >200HU, moderate when 140-200HU and poor when <140HU.

Results

Good image quality was found in 372 patients, moderate in 80 patients and poor in 20 patients. Mean enhancement of the right ventricle cavity was 268HU±102. Patients received an average bolus of 108±24 ml at an average peak flow rate of 6.1±2.2 ml/s. In only three out of 472 patients (0.63%) pathology of the right ventricle was found (dilatation) No other right ventricle pathology was detected.

Conclusion

Right ventricle pathology was detected in three out of 472 patients; the dilatation observed in these three cases may have been picked up even without dedicated enhancement of the right ventricle. Based on our findings, right ventricle enhancement can be omitted during screening coronary CT angiography.     

When Do We Really Need Coronary Calcium Scoring Prior to Contrast-Enhanced Coronary Computed Tomography Angiography? Analysis by Age,Gender and Coronary Risk Factors

Aims

To investigate the value of coronary calcium scoring (CCS) as a filter scan prior to coronary computed tomography angiography (CCTA).

Methods and Results

Between February 2008 and April 2011, 732 consecutive patients underwent clinically indicated CCTA. During this ‘control phase’, CCS was performed in all patients. In patients with CCS≥800, CCTA was not performed. During a subsequent ‘CCTA phase’ (May 2011–May 2012) another 200 consecutive patients underwent CCTA, and CCS was performed only in patients with increased probability for severe calcification according to age, gender and atherogenic risk factors. In patients where CCS was not performed, calcium scoring was performed in contrast-enhanced CCTA images. Significant associations were noted between CCS and age (r = 0.30, p<0.001) and coronary risk factors (χ² = 37.9; HR = 2.2; 95%CI = 1.7–2.9, p<0.001). Based on these associations, a ≤3% pre-test probability for CCS≥800 was observed for males <61 yrs. and females <79 yrs. According to these criteria, CCS was not performed in 106 of 200 (53%) patients during the ‘CCTA phase’, including 47 (42%) males and 59 (67%) females. This resulted in absolute radiation saving of ∼1 mSv in 75% of patients younger than 60 yrs. Of 106 patients where CCS was not performed, estimated calcium scoring was indeed <800 in 101 (95%) cases. Non-diagnostic image quality due to calcification was similar between the ‘control phase’ and the ‘CCTA’ group (0.25% versus 0.40%, p = NS).

Conclusion

The value of CCS as a filter for identification of a high calcium score is limited in younger patients with intermediate risk profile. Omitting CCS in such patients can contribute to further dose reduction with cardiac CT studies.     

Prospectively versus Retrospectively ECG-Gated 256-Slice CT Angiography to Assess Coronary Artery Bypass Grafts — Comparison of Image Quality and Radiation Dose

Objective

In this retrospective non-randomized cohort study, the image quality and radiation dose were compared between prospectively electrocardiogram (ECG)-gated axial (PGA) and retrospectively ECG-gated helical (RGH) techniques for the assessment of coronary artery bypass grafts using 256-slice CT.

Methods

We studied 124 grafts with 577 segments in 64 patients with a heart rate (HR) <85 bpm who underwent CT coronary angiography (CTCA); 34 patients with RGH-CTCA and 30 patients with PGA-CTCA. The image quality of the bypass grafts was assessed by a 5-point scale (1 = excellent to 5 = non-diagnostic) for each segment (proximal anastomosis, proximal, middle, distal course of graft body, and distal anastomosis). Other objective image quality indices such as noise, signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNR) were assessed. Radiation doses were also compared.

Results

Patient characteristics of the two groups were well matched except HR. The HR of the PGA group was lower than that of the RGH group (62.0±5.0 vs. 65.7±7.4). For both groups, over 90% of segments received excellent or good image quality scores and none was non-evaluative. The image quality generally degraded as graft segment approached to distal anastomosis regardless of techniques and graft types. Image quality scores of the PGA group were better than those of the RGH group (1.51±0.53 vs. 1.73±0.62; p<0.001). There was no significantly difference of objective image quality between two techniques, and the effective radiation dose was significantly lower in the PGA group (7.0±1.2 mSv) than that of the RGH group (20.0±4.6 mSv) (p<0.001), with a 65.0% dose reduction.

Conclusions

Following bypass surgery, 256-slice PGA-CTCA is superior to RGH-CTCA in limiting the radiation dose and obtaining better image quality for bypass grafts.     

Informed Consent Prior to Coronary Angiography in a Real World Scenario: What Do Patients Remember?

Background

Patients'' informed consent is legally essential before elective invasive cardiac angiography (CA) and successive intervention can be done. It is unknown to what extent patients can remember previous detailed information given by a specially trained doctor in an optimal scenario as compared to standard care.

Methodology/Principal Findings

In this prospective cohort study 150 consecutive in-patients and 50 out-patients were included before elective CA was initiated. The informed consent was provided and documented in in-patients by trained and instructed physicians the day before CA. In contrast, out-patients received standard information by different not trained physicians, who did not know about this investigation. All patients had to sign a form stating that enough information had been given and all questions had been answered sufficiently. One hour before CA an assessment of the patients'' knowledge about CA was performed using a standard point-by-point questionnaire by another independent physician. The supplied information was composed of 12 potential complications, 3 general, 4 periprocedural and 4 procedural aspects.95% of the patients felt that they had been well and sufficiently informed. Less than half of the potential complications could be remembered by the patients and more patients could remember less serious than life-threatening complications (27.9±8.8% vs. 47.1±11.0%; p<0.001). Even obvious complications like local bleeding could not be remembered by 35% of in-patients and 36% of out-patients (p = 0.87). Surprisingly, there were only a few knowledge differences between in- and out-patients.

Conclusions

The knowledge about CA of patients is vague when they give their informed consent. Even structured information given by a specially trained physician did not increase this knowledge.     

Chronic Total Occlusions in Sweden – A Report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

Introduction

Evidence for the current guidelines for the treatment of patients with chronic total occlusions (CTO) in coronary arteries is limited. In this study we identified all CTO patients registered in the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) and studied the prevalence, patient characteristics and treatment decisions for CTO in Sweden.

Methods and Results

Between January 2005 and January 2012, 276,931 procedures (coronary angiography or percutaneous coronary intervention) were performed in 215,836 patients registered in SCAAR. We identified all patients who had 100% luminal diameter stenosis known or assumed to be ≥3 months old. After exclusion of patients with previous coronary artery bypass graft (CABG) surgery or coronary occlusions due to acute coronary syndrome, we identified 16,818 CTO patients. A CTO was present in 10.9% of all coronary angiographies and in 16.0% of patients with coronary artery disease. The majority of CTO patients were treated conservatively and PCI of CTO accounted for only 5.8% of all PCI procedures. CTO patients with diabetes and multivessel disease were more likely to be referred to CABG.

Conclusion

CTO is a common finding in Swedish patients undergoing coronary angiography but the number of CTO procedures in Sweden is low. Patients with CTO are a high-risk subgroup of patients with coronary artery disease. SCAAR has the largest register of CTO patients and therefore may be valuable for studies of clinical importance of CTO and optimal treatment for CTO patients.     

Is Metabolic Syndrome Predictive of Prevalence,Extent, and Risk of Coronary Artery Disease beyond Its Components? Results from the Multinational Coronary CT Angiography Evaluation for Clinical Outcome: An International Multicenter Registry (CONFIRM)

Although metabolic syndrome is associated with increased risk of cardiovascular disease and events, its added prognostic value beyond its components remains unknown. This study compared the prevalence, severity of coronary artery disease (CAD), and prognosis of patients with metabolic syndrome to those with individual metabolic syndrome components. The study cohort consisted of 27125 consecutive individuals who underwent ≥64-detector row coronary CT angiography (CCTA) at 12 centers from 2003 to 2009. Metabolic syndrome was defined as per NCEP/ATP III criteria. Metabolic syndrome patients (n=690) were matched 1:1:1 to those with 1 component (n=690) and 2 components (n=690) of metabolic syndrome for age, sex, smoking status, and family history of premature CAD using propensity scoring. Major adverse cardiac events (MACE) were defined by a composite of myocardial infarction (MI), acute coronary syndrome, mortality and late target vessel revascularization. Patients with 1 component of metabolic syndrome manifested lower rates of obstructive 1-, 2-, and 3-vessel/left main disease compared to metabolic syndrome patients (9.4% vs 13.8%, 2.6% vs 4.5%, and 1.0% vs 2.3%, respectively; p<0.05), while those with 2 components did not (10.5% vs 13.8%, 2.8% vs 4.5% and 1.3% vs 2.3%, respectively; p>0.05). At 2.5 years, metabolic syndrome patients experienced a higher rate of MACE compared to patients with 1 component (4.4% vs 1.6%; p=0.002), while no difference observed compared to individuals with 2 components (4.4% vs 3.2% p=0.25) of metabolic syndrome. In conclusion, Metabolic syndrome patients have significantly greater prevalence, severity, and prognosis of CAD compared to patients with 1 but not 2 components of metabolic syndrome.     

Coronary Care Units—The Status in California

In order to determine the status of Coronary Care Unit activity in California hospitals, especially as it pertains to nurse training, a survery was conducted by the California State Department of Public Health. More than 95 percent of hospitals that were questioned responded. Only one-third of the hospitals reported they neither had a unit nor plans to build one. All units in operation were either directed by an individual medical director or by a Coronary Care Unit Committee.The survey indicated that in some hospitals with operational units, nurses were not permitted to perform life-saving resuscitative procedures. All operational units reported in-service education programs of some type. Many hospitals indicated they would like to have Coronary Care Unit training programs to which they could send nurses. The reasons why nurses may not perform important resuscitative procedures are discussed as well as the need for Coronary Care Unit training programs for both physicians and nurses in California.     

Coronary artery surgery: are women discriminated against?

OBJECTIVE--To determine whether the sex differences in access to cardiac surgery observed in the United States exist in the United Kingdom. DESIGN--Retrospective analysis of routinely collected data. SETTING--South West Thames and North West Thames regional health authorities. SUBJECTS--8564 patients discharged from hospital with a principal diagnosis of coronary heart disease in 1987-8 in South West Thames region and 15243 discharges in North West Thames region in 1990-1. MAIN OUTCOME MEASURES--Performance of angiography or coronary artery bypass surgery. RESULTS--In all age groups and among patients with a principal diagnosis of either angina or chronic ischaemia men were significantly more likely than women to undergo revascularisation in both regions. Using multiple logistic regression to control for potential clinical and demographic confounders, the male to female odds ratio for revascularisation among all cases was 1.59 (95% confidence interval 1.25 to 2.03) in South West Thames region and 1.47 (1.32 to 1.63) in North West Thames region. CONCLUSION--There appears to be a systematic difference in the treatment received by men and women in the United Kingdom. The reasons for this are uncertain.     

The incidence of “Silent” Coronary Heart Disease

In a group of clinically normal male executives subjected to maximal treadmill stress testing, the occurrence of ischemic st segment responses was in all cases unaccompanied by pain, while in a clinically suspect group a large proportion of those having ischemic st segment responses did not have chest pain.While a significant number of persons have no subjective sensation of pain while having ischemic st segment changes on the electrocardiograph during or after maximal treadmill exercise, occasionally atypical pain may occur during or following exercise. Maximal treadmill stress testing is useful in discovering “silent” coronary artery disease.     

Are There Gender Differences in Coronary Artery Disease? The Malaysian National Cardiovascular Disease Database – Percutaneous Coronary Intervention (NCVD-PCI) Registry

Objectives

To assess whether gender differences exist in the clinical presentation, angiographic severity, management and outcomes in patients with coronary artery disease (CAD).

Methods

The study comprised of 1,961 women and 8,593 men who underwent percutaneous coronary intervention (PCI) and were included in the Malaysian NCVD-PCI Registry from 2007–2009. Significant stenosis was defined as ≥70% stenosis in at least one of the epicardial vessels.

Results

Women were significantly older and had significantly higher rates of diabetes mellitus, hypertension, chronic renal failure, new onset angina and prior history of heart failure whereas smokers and past history of myocardial infarction were higher in men. In the ST-elevation myocardial infarction (STEMI) cohort, more women were in Killip class III-IV, had longer door-to-balloon time (169.5 min. vs 127.3 min, p<0.052) and significantly longer transfer time (300.4 min vs 166.3 min, p<0.039). Overall, women had significantly more left main stem (LMS) disease (1.3% vs 0.6%, p<0.003) and smaller diameter vessels (<3.0 mm: 45.5% vs 34.8%, p<0.001). In-hospital mortality rates for all PCI, STEMI, Non-STEMI (NSTEMI) and unstable angina for women and men were 1.99% vs 0.98%, Odds ratio (OR): 2.06 (95% confidence interval (CI): 1.40 to 3.01), 6.19% vs 2.88%, OR: 2.23 (95% CI: 1.31 to 3.79), 2.90% vs 0.79%, OR: 3.75 (95% CI: 1.58 to 8.90) and 1.79% vs 0.29%, OR: 6.18 (95% CI: 0.56 to 68.83), respectively. Six-month adjusted OR for mortality for all PCI, STEMI and NSTEMI in women were 2.18 (95% CI: 0.97 to 4.90), 2.68 (95% CI: 0.37 to 19.61) and 2.66 (95% CI: 0.73 to 9.69), respectively.

Conclusions

Women who underwent PCI were older with more co-morbidities. In-hospital and six-month mortality for all PCI, STEMI and NSTEMI were higher due largely to significantly more LMS disease, smaller diameter vessels, longer door-to-balloon and transfer time in women.     

Safety and Feasibility of Coronary Stenting in Unprotected Left Main Coronary Artery Disease in the Real World Clinical Practice—A Single Center Experience

Background

This study evaluated the feasibility, safety, and prognostic outcome in patients with significant unprotected left main coronary artery (ULMCA) disease undergoing stenting.

Method and Results

Between January 2010 and December 2012, totally 309 patients, including those with stable angina [13.9% (43/309)], unstable angina [59.2% (183/309)], acute non-ST-segment elevation myocardial infarction (NSTEMI) [24.3% (75/309)], and post-STEMI angina (i.e., onset of STEMI<7 days) [2.6% (8/309)] with significant ULMCA disease (>50%) undergoing stenting using transradial arterial approach, were consecutively enrolled. The patients’ mean age was 68.9±10.8 yrs. Incidences of advance congestive heart failure (CHF) (defined as ≥ NYHA Fc 3) and multi-vessel disease were 16.5% (51/309) and 80.6% (249/309), respectively. Mechanical supports, including IABP for critical patients (defined as LVEF <35%, advanced CHF, or hemodynamically unstable) and extra-corporeal membrane oxygenator (ECMO) for hemodynamically collapsed patients, were utilized in 17.2% (53/309) and 2.6% (8/409) patients, respectively. Stent implantation was successfully performed in all patients. Thirty-day mortality rate was 4.5% (14/309) [cardiac death: 2.9% (9/309) vs. non-cardiac death: 1.6% (5/309)] without significant difference among four groups [2.3% (1) vs. 2.7% (5) vs. 9.3% (7) vs. 12.5% (1), p = 0.071]. Multivariate analysis identified acute kidney injury (AKI) as the strongest independent predictor of 30-day mortality (p<0.0001), while body mass index (BMI) and white blood cell (WBC) count were independently predictive of 30-day mortality (p = 0.003 and 0.012, respectively).

Conclusion

Catheter-based LM stenting demonstrated high rates of procedural success and excellent 30-day clinical outcomes. AKI, BMI, and WBC count were significantly and independently predictive of 30-day mortality.     

Male-Specific Association between a γ-Secretase Polymorphism and Premature Coronary Atherosclerosis

Background

Atherosclerosis is a common multifactorial disease resulting from an interaction between susceptibility genes and environmental factors. The causative genes that contribute to atherosclerosis are elusive. Based on recent findings with a Wistar rat model, we speculated that the γ-secretase pathway may be associated with atherosclerosis.

Methodology/Principal Findings

We have tested for association of premature coronary atherosclerosis with a non-synonymous single-nucleotide polymorphism (SNP) in the γ-secretase component APH1B (Phe217Leu; rs1047552), a SNP previously linked to Alzheimer''s disease. Analysis of a Dutch Caucasian cohort (780 cases; 1414 controls) showed a higher prevalence of the risk allele in the patients (odds ratio (OR) = 1.35), albeit not statistically different from the control population. Intriguingly, after gender stratification, the difference was significant in males (OR = 1.63; p = 0.033), but not in females (OR = 0.50; p = 0.20). Since Phe217Leu-mutated APH1B showed reduced γ-secretase activity in mouse embryonic fibroblasts, the genetic variation is likely functional.

Conclusion/Significance

We conclude that, in a male-specific manner, disturbed γ-secretase signalling may play a role in the susceptibility for premature coronary atherosclerosis.     

Coronary arteriosclerosis in salmon: growing old or growing fast?

A review is presented of what we know and what we suspect regarding the formation of coronary arteriosclerotic lesions in salmonids. Coronary lesions are a fact of life for both Atlantic and Pacific species of migrating salmon. Severe forms of lesions, usually restricted to the main coronary artery, are typically found in the majority of a salmon population when they are spawning. Vascular injury to the coronary artery, as a result of the bulbus arteriosus being excessively distended, is proposed as an initiating mechanism for coronary lesion formation, possibly explaining why severe lesions are restricted primarily to the main coronary artery. Evidence is presented that coronary arteriosclerosis in salmonids develops in immature fish, well before maturation, and progresses with age. Growth and growth rate are implicated in lesion progression. A faster growth rate could produce a more stressful life style, which in turn initiates more coronary vascular injury. Dietary factors, especially polyunsaturated fatty acids (and their metabolites), can significantly stimulate vascular smooth muscle proliferation in the salmon coronary artery, but a possible linkage to the progression of coronary lesions has yet to be studied. Whether coronary lesions negatively impact blood flow to the salmon heart has not been properly studied. Nevertheless, the coronary blood supply to the heart has functional importance when salmon exercise and the coronary flow reserve may be reached when fish swim under mild hypoxic conditions. If coronary arterial lesions do adversely affect blood flow to the heart, the selective effects would be most prominent in years when upstream migration conditions are particularly severe.     

Coronary artery bypass grafting: how much does it cost?

OBJECTIVE: To calculate the cost of coronary artery bypass grafting (CABG) and to compare it with the costs determined in two previous Canadian studies. DESIGN: Retrospective cost-analysis study. SETTING: A tertiary care referral hospital. PATIENTS: Fifty patients who had undergone successful triple and quadruple CABG between Jan. 3 and 30, 1989. MAIN RESULTS: The cost of CABG per patient varied from $10,982 to $33,676 (mean $14,328) (in 1988 Canadian dollars). The cost tended to increase with age and number of vessels grafted. Compared with the patients in the two previous Canadian studies our patients were older, had more vessels grafted and cost more to treat, even after the total hospital costs were adjusted for inflation. CONCLUSIONS: The population undergoing CABG is changing: it is older and has more diseased vessels. These changes have had a significant impact on the cost of CABG. Further study is required to determine the outcome and benefit of CABG in this group of patients.     

Coronary artery disease: Are men and women created equal?

Background: Ischemic heart disease in women is a difficult issue in cardiovascular medicine, mainly because of our lack of understanding of the early-stage mechanisms and symptoms. A better and earlier understanding of the pathophysiology of coronary artery disease (CAD) in women will enable us to detect ischemic heart disease earlier and prevent adverse clinical outcomes.Objectives: The aims of this article were to describe the phenomenon of ischemic heart disease in women, increase awareness of the difference between men and women in relation to ischemic heart disease, improve our understanding of the mechanisms that cause this difference, and identify new approaches for better and earlier detection and treatment of CAD in women.Methods: We conducted a search of the PubMed database for double-blind studies on the mechanistic pathways of CAD in women published in English within the past 10 years and epidemiologic studies published since 1970. Search terms included women and coronary artery disease and ischemic heart disease in women.Results: The literature search revealed 30 peer-reviewed articles pertaining to this issue. The incidence of CAD was markedly lower in women <60 years of age than in older women. After 60 years of age, the rate of CAD increased and reached the rate seen among men by the 8th decade of life. The gender difference in atherosclerosis in the coronary tree was particularly large in patients <55 years of age and remained large at older ages. The gender difference in the coronary bed was strikingly larger than in other vascular beds. Intensive risk-factor modification had a similar effect on plaque progression in both men and women. Coronary endothelial dysfunction appeared to be related to cardiovascular morbidity and mortality in women as well as in men, and because endothelial dysfunction could be modified, it appeared that the prognosis could be improved by appropriate management. A strong association was found between body mass index (BMI) and metabolic status, but only the metabolic syndrome was associated with CAD. Physical activity was independently associated with fewer risk factors, less CAD, and fewer adverse events in women; however, obesity was not associated with these outcomes.Conclusions: Results of the identified studies suggest that reduction of risk factors is a common approach to fighting heart disease in both sexes. It appears that for women, weight and BMI are not as important as previously thought, but physical exercise and fitness are very important and can change risk factors and clinical outcomes more than any other known intervention. Data suggest that global inflammation may play an important role in women and may predict cardiovascular outcome in women much better than the traditional risk factors that have been used and proved for men.     

Digital Subtraction Angiography Imaging Characteristics of Patients with Extra–Intracranial Atherosclerosis and Its Relationship to Stroke

To investigate the angiographic characteristics and clinical features in patients with suspected extra–intracranial atherosclerosis in a large cohort of Chinese population. On the basis of digital subtraction angiography characteristics, pathological morphology of extra–intracranial atherosclerosis was divided into tortuosity, kinking, coiling, and stenosis in 2,218 individuals aged 45–89 years. The degree of stenosis was further divided into low-grade (<30 %), intermediate-grade (30–69 %), and high-grade stenosis (≥70 %). Clinical manifestations were divided into transient ischemic attack, cerebral infarction and cerebral hemorrhage. The prevalence of tortuosity and stenosis were significantly higher in the extracranial arterial system than that of intracranial arterial system. The prevalence of tortuosity and kinking were significantly higher on the left side than the right side. The prevalence of mild and moderate stenosis in the internal carotid artery was significantly higher in the left side than the right side. The incidence of cerebral infarction was significantly higher in the internal carotid arterial (ICA) system than the vertebrobasilar arterial (VBA) system. Tortuosity is a common carotid abnormality in the Chinese population. The prevalence of ICA tortuosity is higher than that of VBA. The incidence of cerebral infarction in each atherosclerosis group was significantly higher in ICA than that of VBA. The prevalence of stroke is higher in the ICA system than the VBA system. Kinkings and coilings may not have a clinical significance if these lesions are not associated with atheromatous plaques or carotid stenosis.