Cardiac catheterization in morbidly obese patients

Transcarotid versus transfemoral access for cerebrovascular intervention: protocol for a systematic review and meta-analysis

INTRODUCTION

Cerebrovascular intervention is an excellent option to treat cerebrovascular diseases. Interventional access is a prerequisite and a foundation for cerebrovascular intervention, which is crucial to the success of an intervention. Although transfemoral arterial access (TFA) has become a popular and acceptable method of access for cerebrovascular angiography and intervention in clinical practice, it has some drawbacks that limit the usage in cerebrovascular interventions. Therefore, transcarotid arterial access (TCA) has been developed in cerebrovascular interventions. We aim to conduct a systematic review to compare the safety and efficacy of TCA with TFA for cerebrovascular intervention.

METHODS AND ANALYSIS

In this protocol, Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols were followed. PubMed, Embase, Web of Science and the Cochrane Central Register of Controlled Trials will be searched mainly from 1 January 2004, to the formal search date. Additionally, reference lists and clinical trial registries will be searched. We will include clinical trials with more than 30 participants, which reported the endpoints of stroke, death and myocardial infarction. Two investigators will independently select studies, extract data and assess bias risk. A standardised mean difference with 95% CI will be presented for continuous data, and a risk ratio with 95% CI will be presented for dichotomous data. On inclusion of sufficient studies, subgroup analysis and sensitivity analysis will be conducted. The funnel plot and Egger's test will be used to assess publication bias.

ETHICS AND DISSEMINATION

As only published sources will be used in this review, ethical approval is not required. We will publish the results in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42022316468.

Obesity and Cardiovascular Disease: A Scientific Statement From the American Heart Association

The global obesity epidemic is well established, with increases in obesity prevalence for most countries since the 1980s. Obesity contributes directly to incident cardiovascular risk factors, including dyslipidemia, type 2 diabetes, hypertension, and sleep disorders. Obesity also leads to the development of cardiovascular disease and cardiovascular disease mortality independently of other cardiovascular risk factors. More recent data highlight abdominal obesity, as determined by waist circumference, as a cardiovascular disease risk marker that is independent of body mass index. There have also been significant advances in imaging modalities for characterizing body composition, including visceral adiposity. Studies that quantify fat depots, including ectopic fat, support excess visceral adiposity as an independent indicator of poor cardiovascular outcomes. Lifestyle modification and subsequent weight loss improve both metabolic syndrome and associated systemic inflammation and endothelial dysfunction. However, clinical trials of medical weight loss have not demonstrated a reduction in coronary artery disease rates. In contrast, prospective studies comparing patients undergoing bariatric surgery with nonsurgical patients with obesity have shown reduced coronary artery disease risk with surgery. In this statement, we summarize the impact of obesity on the diagnosis, clinical management, and outcomes of atherosclerotic cardiovascular disease, heart failure, and arrhythmias, especially sudden cardiac death and atrial fibrillation. In particular, we examine the influence of obesity on noninvasive and invasive diagnostic procedures for coronary artery disease. Moreover, we review the impact of obesity on cardiac function and outcomes related to heart failure with reduced and preserved ejection fraction. Finally, we describe the effects of lifestyle and surgical weight loss interventions on outcomes related to coronary artery disease, heart failure, and atrial fibrillation.

False-positive stress echocardiograms: Predictors and prognostic relevance

BACKGROUND

Recent studies indicate that the pretest likelihood of significant coronary artery disease (CAD) (≥50% luminal stenosis) is over-estimated and that the frequency and severity of positive stress tests have been decreasing. This suggests an increased prevalence of false-positive (FP) stress tests. The aims of this retrospective study were to investigate the predictors of FP stress echocardiography (SE) and to compare the outcomes of patients with FP results to those with true-positive (TP) results.

METHODS

Patients who underwent SE between 2013 and 2017 in a tertiary-care center were reviewed. Included were patients aged ≥40years who had cardiac catheterization (CC) within 1year of the index stress test. SE was considered FP if a new or worsening wall motion abnormality was present in the absence of significant corresponding CAD.

RESULTS

Of the 5100 patients with SE, 1069 satisfied inclusion criteria. A total of 305 patients had positive SE results; of which 162 (53%) were FP. Logistic regression revealed that female gender (p=0.009), the absence of diabetes (p=0.03), the absence of a personal history of CAD (p=0.004), and lower stress WMSI (p=0.03) were independently associated with FP results. Patients with FP results on SE had similar all-cause mortality to those with TP results.

CONCLUSIONS

Accounting for predictors of FP findings on SE could improve the interpretation of SE results and limit the use of unnecessary CC. Furthermore, patients with FP results on SE could benefit from aggressive risk factor control and careful clinical follow-up.

Retrograde 3D rotational venography (3DRV) for venous sinus stent placement in idiopathic intracranial hypertension

Background

Dural venous sinus stenting has emerged as an effective and durable treatment for idiopathic intracranial hypertension (IIH). Improved visualization of the venous sinuses can improve stent placement.

Methods

We present two cases of IIH treated with venous sinus stenting in which retrograde three-dimensional rotational venography (3DRV) provided superior anatomical details of the venous sinuses for optimal sizing and positioning of stent.

Results

Comparison of pre-stent 3DRV with post-stent contrast-enhanced flat panel detector CT allowed confirmation of stent placement and the result of stenosis dilation.

Conclusion

This 3DRV technique provides precise visualization of venous sinus stenosis prior to stenting without the need for arterial cerebral angiography during the treatment course.

Outcomes of Obese and Morbidly Obese Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

The risks of percutaneous coronary intervention (PCI) in obese and particularly morbidly obese patients remain uncertain.

METHODS

1082 consecutive patients were categorised as non-obese (NO, body mass index (BMI) <30kg/m², n=688), obese (O, BMI 30-40kg/m², n=354) or morbidly obese (MO, BMI ≥40kg/m², n=40). Demographic and procedural information was collated. Monte Carlo simulations modelled radiation dosimetric data.

RESULTS

Obese and morbidly obese patients were younger (p=0.016), more frequently female (p=0.036), more frequently diabetic (p<0.0001), with better renal function (p<0.0001), and prior PCI (p=0.01). There was no difference in major adverse cardiovascular or cerebrovascular events (MACCE) (NO=1.2%, O=0.8%, MO=2.5%, p=NS), acute kidney injury, bleeding, length of stay, 30-day readmission or 30-day mortality. Obese and morbidly obese patients received increased contrast (NO=180 [150-230]mL, O=190 [160-250]mL, MO=200 [165-225]mL, p=0.016), dose area product (NO=75.56 [50.61-113.69]Gycm², O=116.4 [76.11-157.82]Gycm², MO=125.62 [92.22-158.81]Gycm², p<0.0001), entrance air kerma (NO=1439.42 [977.0-2075.5]mGy, O=2111.63 [1492.0-3011.0]mGy, MO=2376.0 [1700.0-3234.42]mGy, p<0.0001), and peak skin dose (NO=1439.42 [977.0-2075.5], O=2111.63 [1492.0-3011.0], MO=2376.0 [1700.0-3234.42], p<0.0001). Effective radiation dose increased in obese patients (NO=20.9±14.9mSv, O=27.4±17.1mSv, MO=24.1±12.6mSv, p<0.0001 for NO vs O, p=0.449 for NO vs MO).

CONCLUSIONS

Percutaneous coronary intervention can be performed in obese and morbidly obese patients without elevated risk for most clinical outcomes. However, radiation increases above levels that could cause both transient and late effects. Strategies should be pursued to minimise radiation dose.

Optimizing care for the obese patient in interventional radiology

With the rising epidemic of obesity, interventional radiologists are treating increasing numbers of obese patients, as comorbidities associated with obesity preclude more invasive treatments. These patients are at heightened risk of vascular and oncologic disease, both of which often require interventional radiology care. Obese patients pose unique challenges in imaging, technical feasibility, and periprocedural monitoring. This review describes the technical and clinical challenges posed by this population, with proposed methods to mitigate these challenges and optimize care.

Controversies in complex percutaneous coronary intervention: radial versus femoral

INTRODUCTION

Evolution in the technology used in the cardiac catheterization laboratory has permitted a migration from the femoral to radial artery access for many interventional procedures while concurrently improving outcomes. As a disruptive technology, transradial access has been associated with several controversies including a dichotomous relationship with femoral access. Areas covered: Several different patient subsets along with perceived technical challenges in interventional cardiology are reviewed with regard to the issue of access site. Evolving technological improvements germane to transradial techniques are also discussed as garnered from the literature of recent clinical trials and reports. Expert commentary: Radial techniques have been enhanced by newer technology and the spread of knowledge. Fusion of radial techniques with those of the femoral approach is evolving into a unifying concept of using the access that is most appropriate for the patient. No one access technique can cover all clinical subsets of patients. There is a need for complimentary access skillsets for even the most advanced cardiovascular technology used in the cardiac catheterization laboratory if the patients' outcomes are to be idealized.

Feasibility of SPECT myocardial perfusion imaging in the super-obese using a multi-head semiconductor camera with attenuation correction

BACKGROUND

Obesity is not only associated with an increased risk of coronary artery disease, but also decreases the accuracy of many diagnostic modalities pertinent to this disease. Advances in myocardial perfusion imaging (MPI) have mitigated somewhat the effects of obesity, although the feasibility of MPI in the super-obese (defined as a BMI > 50) is currently untested. We undertook this study to assess the practicality of MPI in the super-obese using a multi-headed solid-state gamma camera with attenuation correction.

METHODS

We retrospectively identified consecutive super-obese patients referred for MPI at our institution. The images were interpreted by 3 blinded, experienced readers and graded for quality and diagnosis, and subjectively evaluated the contribution of attenuation correction. Clinical follow-up was obtained from review of medical records.

RESULTS

72 consecutive super-obese patients were included. Their BMI ranged from 50 to 67 (55.7 ± 5.1). Stress image quality was considered good or excellent in 45 (63%), satisfactory in 24 (33%), poor in 3 (4%), and uninterpretable in 0 patients. Rest images were considered good or excellent in 34 (49%), satisfactory in 23 (33%), poor in 13 (19%), and uninterpretable in 0 patients. Attenuation correction changed the interpretation in 34 (47%) of studies.

CONCLUSIONS

MPI is feasible and provides acceptable image quality for super-obese patients, although it may be camera and protocol dependent.

Obesity and coronary artery disease: evaluation and treatment

With the increasing prevalence of obesity, clinicians are now facing a growing population of patients with specific features of clinical presentation, diagnostic challenges, and interventional, medical, and surgical management. After briefly discussing the effect of obesity on atherosclerotic burden in this review, we will focus on strategies clinicians might use to ensure better outcomes when performing revascularization in obese and severely obese patients. These patients tend to present comorbidities at a younger age, and their anthropometric features might limit the use of traditional cardiovascular risk stratification approaches for ischemic disease. Alternative techniques have emerged, especially in nuclear medicine. Positron emission tomography-computed tomography might be the diagnostic imaging technique of choice. When revascularization is considered, features associated with obesity must be considered to guide therapeutic strategies. In percutaneous coronary intervention, a radial approach should be favoured, and adequate antiplatelet therapy with new and more potent agents should be initiated. Weight-based anticoagulation should be contemplated if needed, with the use of drug-eluting stents. An "off-pump" approach for coronary artery bypass grafting might be preferable to the use of cardiopulmonary bypass. For patients who undergo bilateral internal thoracic artery grafting, harvesting using skeletonization might prevent deep sternal wound infections. In contrast to percutaneous coronary intervention, lower surgical bleeding has been observed when lean body mass is used for perioperative heparin dose determination.

Transradial approach to cardiovascular interventions: an update

Background Since the first cardiac catheterization in 1929, the procedure has continually evolved with advances in understanding, capabilities, and ease of operation. Though historically performed by cut down of the brachial artery, cardiologists soon learned that transfemoral access was both easier to perform and more efficacious with regard to patient outcome. In the last 20 years, the transradial approach has been adopted, and is being utilized with increasing frequency. Methods We conducted a survey of literature published concerning safety, efficacy, cost-effectiveness, and global uptake of transradial catheterization with specific attention to how transradial interventions compare with transfemoral interventions. Results This review of literature indicates that when performed by an experienced interventionalist, radial catheterization is as effective as femoral catheterization and has additional benefits of shorter length of hospital stay and reduced patient costs. Transradial access is superior to transfemoral access in some, but not all, clinical scenarios; in addition, it is an effective alternative for catheterization in patients contraindicated for transfemoral procedures. Adoption of radial access in the United States is at a faster rate than previously expected, though rate of use varies drastically worldwide. Conclusion The transradial approach is an excellent option for carrying out cardiovascular interventions, and will be adopted by more cardiologists in the upcoming years.

Prognostic value of normal stress echocardiography in obese patients

BACKGROUND

Chest pain is a common problem in obese patients. Because of the body habitus, the results of noninvasive evaluation for CAD may be limited in this group.

METHODS

We reviewed the records of 1446 consecutive patients who had undergone clinically indicated stress echocardiography (SE). We compared major adverse cardiac events (MACE; myocardial infarction, cardiac intervention, cardiac death, subsequent hospitalization for cardiac events, and emergency department visits) at 1 year in normal weight, overweight, and obese subjects with normal SE.

RESULTS

Excluding patients with an abnormal and indeterminate SE and those who were lost to follow-up, a retrospective analysis of 704 patients was performed. There were 366 obese patients (BMI ≥ 30), 196 overweight patients (BMI 25-29.9), and 142 patients with normal BMI (18.5-24.9). There was no MACE in the groups at 1-year follow-up after a normal SE.

CONCLUSIONS

In obese patients including those with multiple risk factors and symptoms concerning for cardiac ischemia, stress echocardiography is an effective and reliable noninvasive tool for identifying those with a low 1-year risk of cardiac events.

A multicenter, prospective study to evaluate the use of contrast stress echocardiography in early menopausal women at risk for coronary artery disease: trial design and baseline findings

AIMS

This multisite prospective trial, Stress Echocardiography in Menopausal Women At Risk for Coronary Artery Disease (SMART), aimed to evaluate the prognostic value of contrast stress echocardiography (CSE), coronary artery calcification (CAC), and cardiac biomarkers for prediction of cardiovascular events after 2 and 5 years in early menopausal women experiencing chest pain symptoms or risk factors. This report describes the study design, population, and initial test results at study entry.

METHODS

From January 2004 through September 2007, 366 early menopausal women (age 54±5 years, Framingham risk score 6.51%±4.4 %, range 1%-27%) referred for stress echocardiography were prospectively enrolled. Image quality was enhanced with an ultrasound contrast agent. Tests for cardiac biomarkers [high-sensitivity C-reactive protein (hsCRP), atrial natriuretic protein (ANP), brain natriuretic protein (BNP), endothelin (ET-1)] and cardiac computed tomography (CT) for CAC were performed.

RESULTS

CSE (76% exercise, 24% dobutamine) was abnormal in 42 women (11.5%), and stress electrocardiogram (ECG) was positive in 22 women (6%). Rest BNP correlated weakly with stress wall motion score index (WMSI) (r=0.189, p<0.001). Neither hsCRP, ANP, endothelin, nor CAC correlated with stress WMSI. Predictors of abnormal CSE were body mass index (BMI), diabetes mellitus, family history of premature coronary artery disease (CAD), and positive stress ECG. Twenty-four women underwent clinically indicated coronary angiography (CA); 5 had obstructive (≥50%), 15 had nonobstructive (10%-49%), and 4 had no epicardial CAD.

CONCLUSIONS

The SMART trial is designed to assess the prognostic value of CSE in early menopausal women. Independent predictors of positive CSE were BMI, diabetes mellitus, family history of premature CAD, and positive stress ECG. CAC scores and biomarkers (with the exception of rest BNP) were not correlated with CSE results. We await the follow-up data.

Image quality of low-dose CCTA in obese patients: impact of high-definition computed tomography and adaptive statistical iterative reconstruction

The accuracy of coronary computed tomography angiography (CCTA) in obese persons is compromised by increased image noise. We investigated CCTA image quality acquired on a high-definition 64-slice CT scanner using modern adaptive statistical iterative reconstruction (ASIR). Seventy overweight and obese patients (24 males; mean age 57 years, mean body mass index 33 kg/m(2)) were studied with clinically-indicated contrast enhanced CCTA. Thirty-five patients underwent a standard definition protocol with filtered backprojection reconstruction (SD-FBP) while 35 patients matched for gender, age, body mass index and coronary artery calcifications underwent a novel high definition protocol with ASIR (HD-ASIR). Segment by segment image quality was assessed using a four-point scale (1 = excellent, 2 = good, 3 = moderate, 4 = non-diagnostic) and revealed better scores for HD-ASIR compared to SD-FBP (1.5 ± 0.43 vs. 1.8 ± 0.48; p < 0.05). The smallest detectable vessel diameter was also improved, 1.0 ± 0.5 mm for HD-ASIR as compared to 1.4 ± 0.4 mm for SD-FBP (p < 0.001). Average vessel attenuation was higher for HD-ASIR (388.3 ± 109.6 versus 350.6 ± 90.3 Hounsfield Units, HU; p < 0.05), while image noise, signal-to-noise ratio and contrast-to noise ratio did not differ significantly between reconstruction protocols (p = NS). The estimated effective radiation doses were similar, 2.3 ± 0.1 and 2.5 ± 0.1 mSv (HD-ASIR vs. SD-ASIR respectively). Compared to a standard definition backprojection protocol (SD-FBP), a newer high definition scan protocol in combination with ASIR (HD-ASIR) incrementally improved image quality and visualization of distal coronary artery segments in overweight and obese individuals, without increasing image noise and radiation dose.

Characteristics and outcomes of patients with abnormal stress echocardiograms and angiographically mild coronary artery disease (<50% stenoses) or normal coronary arteries

BACKGROUND

Abnormal cardiac stress imaging findings are not always associated with angiographically significant coronary artery disease. The outcomes of patients with such false-positive findings have not been extensively examined. The aim of this retrospective study was to describe the characteristics and outcomes of patients with abnormal stress echocardiographic findings who had false-positive results compared with those who had true-positive results.

METHODS

Of 1,477 consecutive patients (mean age, 66 +/- 12 years; 61% men) with abnormal stress echocardiographic findings who underwent coronary arteriography within 30 days, death from any cause was ascertained.

RESULTS

At coronary arteriography, 997 patients (67.5%) had true-positive results, defined by the presence of angiographically significant coronary artery disease (> or = 50% stenoses), and 480 (32.5%) had false-positive results, defined by <50% stenoses or normal coronary arteries. Of the subgroup of patients with markedly abnormal stress echocardiographic findings (n = 605), 28% had <50% stenoses or normal coronary arteries. During an average follow-up period of 2.4 +/- 1.0 years, there were 140 deaths. The adjusted likelihood of subsequent death for patients with <50% stenoses compared to patients with > or = 50% stenoses after abnormal stress echocardiography was 1.05 (95% confidence interval, 0.86-1.31; P = .62).

CONCLUSIONS

A sizable proportion of patients with abnormal stress echocardiographic results who are referred for coronary angiography have false-positive findings. The outcomes of patients with false-positive results were similar to those of patients with true-positive results. This finding suggests that patients with false-positive results on stress echocardiography should still receive intensive risk factor management and careful clinical follow-up.

Impact of obesity on hospitalized patients

Obesity is increasing at an alarming rate worldwide and is a risk factor for cardiac disease, diabetes, and stroke. This provides a challenge for the physicians caring for this patient population in the hospital. Skin integrity, medication dosing, testing, and nutrition are all altered by obesity. We summarize some of the current data on caring for the obese inpatient. Unfortunately, few data on this unique inpatient population exist.

Body weight limitations of United States cardiac catheterization laboratories including restricted access for the morbidly obese

A telephone survey was performed to determine the current weight limits of cardiovascular catheterization laboratories (n = 94) in the United States. The minimum, mean, and maximum weight limits of the catheterization laboratories in this survey were 160, 198.9, and 250 kg (350, 437.5, and 550 lb), respectively. Twenty-two percent of respondents (n = 21) referred to other institutions when asked what they did when patients were too heavy, and 70% of respondents (n = 66) could not provide an answer. In this population, 5.2 +/- 3.4 patients/hospital/year were rejected for being over the weight limit. In conclusion, these results provide useful information for the future management of this growing population.

Impact of obesity and bariatric surgery on cardiovascular disease

Morbid obesity is a growing public health concern with multiple associated cardiovascular comorbidities. Bariatric surgery has emerged as a safe and effective treatment for morbidly obese patients at risk for, or already suffering from, cardiovascular disease. Weight loss induced by the surgery has been shown to improve cardiovascular risk factors, cardiac structure and function, and the clinical course of established cardiovascular disease. The role of adipocyte-derived cytokines in mediating cardiovascular pathophysiology in obesity-and its modulation after weight loss-is under active investigation.

Normal coronary arteries in patients with systolic heart failure who have higher body mass index

BACKGROUND

Previous research has shown an association between higher body mass index (BMI) and lower mortality in patients with heart failure (HF).

METHODS

We compared the prevalence of angiographic coronary artery disease (CAD) and risk factors in obese versus non-obese patients with HF. Eighty-four consecutive patients with systolic HF who underwent coronary angiography in a single institution were categorized by BMI into non-obese (BMI < 30, n = 42) and obese (BMI >or= 30, n = 42) subjects.

RESULTS

Chi-square analysis demonstrated a greater prevalence of normal coronary arteries and a lesser prevalence of CAD in the obese patients compared with the non-obese patients (64% [27/42] of obese patients vs 43% [18/42] non-obese patients had normal coronary arteries, P < .05). Among the obese patients, the subgroup with normal coronary arteries had a higher BMI (39 vs 32, P < .001) and was younger (51 vs 63 years, P < .005) compared with those with CAD. Although the prevalence of significant CAD (>50% diameter stenosis) was similar between obese and non-obese patients, the obese subgroup had a lower high-density lipoprotein (39 vs 49 mg/dL, P < .05).

CONCLUSIONS

Angiographically normal coronary arteries were more prevalent in patients with systolic HF who have a higher BMI.

SPECT myocardial perfusion imaging in morbidly obese patients: Image quality, hemodynamic response to pharmacologic stress, and diagnostic and prognostic value

BACKGROUND

Obesity is a growing epidemic in the United States, and little is known about the characteristics of the morbidly obese population (body mass index [BMI] > or = 40 kg/m2) undergoing stress myocardial perfusion imaging (MPI).

METHODS AND RESULTS

We retrospectively reviewed all consecutive morbidly obese patients without known coronary artery disease presenting for a clinically indicated technetium 99m (Tc-99m) gated stress single photon emission computed tomography imaging study over a 42-month period. Studies were analyzed for image quality, for the contribution of attenuation correction to image interpretation, and for the hemodynamic response to pharmacologic stress. In patients who subsequently had cardiac catheterization, the results were compared with those from the initial MPI study, and the Social Security Death Index and hospital medical records were searched to the assess survival rate in the entire cohort. A total of 433 patients were identified with a mean BMI of 47.3 +/- 8 kg/m2 and a mean Tc-99m stress dose of 35.6 +/- 5.4 mCi. Image quality was good in 61% of the patients, adequate in 37%, and poor in 2%. It was found to be dependent on the stressor used (better with exercise) but did not correlate with increasing weight or BMI. Attenuation correction was used in 95% of the studies reviewed and was helpful for image interpretation in 60%. The heart rate response to dipyridamole and adenosine was more pronounced and the blood pressure response to dipyridamole was less pronounced in morbidly obese patients compared with nonobese control patients. In the 43 patients who underwent catheterization, stress MPI had a sensitivity of 95% and negative predictive value of 80%. Kaplan-Meier survival analysis at 1 year showed a significant difference in survival rate of 98.3% for normal MPI studies and 94.0% for abnormal MPI studies (P = .02).

CONCLUSION

Diagnostic-quality single photon emission computed tomography imaging is feasible in the majority (98%) of morbidly obese patients with the use of a dual-head camera, attenuation correction, and high stress Tc-99m tracer doses. Exercise stress was associated with better image quality. The prognostic value of a normal MPI study in this population appears to be less favorable than in non-morbidly obese patients.

Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss: an update of the 1997 American Heart Association Scientific Statement on Obesity and Heart Disease from the Obesity Committee of the Council on Nutrition, Physical Activity, and Metabolism

Obesity is becoming a global epidemic in both children and adults. It is associated with numerous comorbidities such as cardiovascular diseases (CVD), type 2 diabetes, hypertension, certain cancers, and sleep apnea/sleep-disordered breathing. In fact, obesity is an independent risk factor for CVD, and CVD risks have also been documented in obese children. Obesity is associated with an increased risk of morbidity and mortality as well as reduced life expectancy. Health service use and medical costs associated with obesity and related diseases have risen dramatically and are expected to continue to rise. Besides an altered metabolic profile, a variety of adaptations/alterations in cardiac structure and function occur in the individual as adipose tissue accumulates in excess amounts, even in the absence of comorbidities. Hence, obesity may affect the heart through its influence on known risk factors such as dyslipidemia, hypertension, glucose intolerance, inflammatory markers, obstructive sleep apnea/hypoventilation, and the prothrombotic state, in addition to as-yet-unrecognized mechanisms. On the whole, overweight and obesity predispose to or are associated with numerous cardiac complications such as coronary heart disease, heart failure, and sudden death because of their impact on the cardiovascular system. The pathophysiology of these entities that are linked to obesity will be discussed. However, the cardiovascular clinical evaluation of obese patients may be limited because of the morphology of the individual. In this statement, we review the available evidence of the impact of obesity on CVD with emphasis on the evaluation of cardiac structure and function in obese patients and the effect of weight loss on the cardiovascular system.

Method for coronary angiography in morbidly obese patients

Cardiac catheterization in morbidly obese patients is difficult. In addition to problems regarding vascular access and radiographic penetration of the chest, the engineering parameters and physical limitations of the table and its supporting structures may limit these patients' ability to undergo clinically indicated coronary angiography. We describe a method for cardiac catheterization in which much of the obese patient's body weight is supported on a stretcher placed at right angles to the catheterization table, with only the thorax on the table under the image intensifier. Using this method, five consecutive successful diagnostic procedures and one coronary stent procedure have been performed without complication. Limitations of this procedure include inability to achieve the normal variety of angiographic views due to constraints on image intensifier rotation and skew.

Transradial coronary angiography in patients with contraindications to the femoral approach: An analysis of 500 cases

The transradial approach to coronary angiography is considered by some to be a route of choice, by others to be a route that should be used only where there are relative contraindications to the femoral approach. We present the largest series to date of patients in whom transradial coronary angiography was undertaken specifically because of contraindications to the femoral approach. Since 1995, patients at this cardiothoracic center have been considered for a transradial approach to coronary angiography if there were relative contraindications to the femoral route. Data from 500 patients was prospectively collected. Patients were aged 66 +/- 9 years; 72% were male. Indications for the radial approach included peripheral vascular disease (305), therapeutic anticoagulation (77), musculoskeletal (59), and morbid obesity (32). Sixty-eight patients (14%) required a radial procedure following a failed femoral approach. Access was right radial 291 (58%), left radial 209 (42%). Eighteen operators were involved, but two operators undertook 355 (71%) of the cases. Catheter gauge was 6 Fr (n = 243; 49%), 5 Fr (219; 43%), and 4 Fr (29; 6%). The procedure was successful in 463 cases [92.6%; 88.2% for nonmajority vs. 94.4% (P < 0.05) for the two majority operators]. Success in males (93.6%) significantly exceeded that in females (90.1%; P < 0.05). In-catheter-laboratory duration was 45 +/- 17 min; fluoroscopy time, 7.5 +/- 6 min; radiation dose, 40 +/- 23 CGy. The procedure was without incident in 408 cases (82%). There were procedural difficulties in 18% of cases, including radial artery spasm (12%) and vasovagal response (5%). The incidence was higher with 6 Fr catheters (23%) than with 5/4 Fr (15%; P < 0.05). Major procedural complications occurred in three cases: brachial artery dissection in one and cardiac arrest in two. Postprocedure major vascular complications numbered three: claudicant pain on handgrip in one, ischemic index finger (with subsequent terminal phalanx amputation due to osteomyelitis) in one, and ischemic hand for 4 hr in one. Patients with contraindications to the femoral approach form a high-risk group. In these patients, transradial cardiac catheterization can be performed successfully and with a low risk of major complications. Minor adverse features remain frequent, occurring in one in five cases, though difficulties are minimized both with increasing operator experience and smaller sheath diameter.