Limited clinical utility of CT coronary angiography in a district hospital setting.

BACKGROUND: Studies have demonstrated considerable accuracy of multi-slice CT coronary angiography (MSCT-CA) in comparison to invasive coronary angiography (I-CA) for evaluating coronary artery disease (CAD). The extent to which published MSCT-CA accuracy parameters are transferable to routine practice beyond high-volume tertiary centres is unknown. AIM: To determine the accuracy of MSCT-CA for the detection of CAD in a Scottish district general hospital. DESIGN: Prospective study of diagnostic accuracy. METHOD: One hundred patients with suspected CAD recruited from two Glasgow hospitals underwent both MSCT-CA (Philips Brilliance 40 × 0.625 collimation, 50-200 ms temporal resolution) and I-CA. Studies were reported by independent, blinded radiologists and cardiologists and compared using the AHA 15-segment model. RESULTS: Of 100 patients [55 male, 45 female, mean (SD) age 58.0 (10.7) years], 59 and 41% had low-intermediate and high pre-test probabilities of significant CAD, respectively. Mean (SD) heart rate during MSCT-CA was 68.8 (9.0) bpm. Fifty-seven per cent of patients had coronary artery calcification and 35% were obese. Patient prevalence of CAD was 38%. Per-patient sensitivity, specificity, positive and negative (NPV) predictive values for MSCT-CA were 92.1, 47.5, 52.2 and 90.6%, respectively. NPV was reduced to 75.0% in the high pre-test probability group. Specificity was compromised in patients with sub-optimally controlled heart rates, calcified arteries and elevated BMI. CONCLUSION: Forty-Slice MSCT-CA has a high NPV for ruling out significant CAD when performed in a district hospital setting in patients with low-intermediate pre-test probability and minimal arterial calcification. Specificity is compromised by clinically appropriate strategies for dealing with unevaluable studies. Effective heart rate control during MSCT-CA is imperative. National guidelines should be utilized to govern patient selection and direct MSCT-CA reporter training to ensure quality control.

Transthoracic echocardiography: a survey of current practice in the UK.

BACKGROUND: Echocardiography is one of the cornerstones of cardiovascular investigation. The escalating demands on echocardiography services necessitate close examination of how we organize our departments on a day-to-day basis, in order to provide a consistent, high-quality service. AIM: To evaluate current transthoracic echocardiography practice in the UK. DESIGN: National postal survey. METHODS: A questionnaire was sent to the chief cardiac physiologist (CP) of every hospital in the UK with echocardiographic facilities. RESULTS: Three hundred and thirty six echocardiographic departments were identified. One hundred and twenty six (37.5%) completed questionnaires were returned. In 87% of hospitals, CPs both performed and reported over 80% of echocardiograms. Fifty-seven percent of CPs and 22% of doctors performing echocardiography held an accreditation in echocardiography. Only 60% of hospitals had formal criteria that had to be met prior to an operator being allowed to report echocardiograms unsupervised. Fewer than half of hospitals regularly audited their echocardiography service. Both outpatient and inpatient waiting times for echocardiography were highly variable and frequently excessive. Fewer than half of hospitals used modern techniques for assessing diastolic function, mechanical dyssynchrony or severity of mitral regurgitation. CONCLUSION: In the UK, many transthoracic echocardiograms are performed and reported by operators without formally assessed competence. Fewer than half of hospitals regularly audited their service or used modern echocardiographic techniques. Services are likely to be improved by developing and instituting mandatory national guidelines.

Pericardiocentesis practice in the United Kingdom.

BACKGROUND: Pericardial effusions frequently present challenging clinical dilemmas. Whether or not to drain an effusion, and if so by what method, are two common decisions facing cardiologists. We performed a survey to evaluate pericardiocentesis practice in the United Kingdom (UK). METHODS: A total of 640 questionnaires were sent to all cardiologists in the UK Directory of Cardiology in March 2003. RESULTS: A total of 274 (43%) completed questionnaires were returned, 88% from consultants, equally distributed between tertiary referral centres and district general hospitals. More than 1500 procedures were performed, largely using a paraxiphoid approach (89%). Clinical tamponade was the commonest indication for pericardiocentesis (83%). However, the majority of respondents (69%) considered echocardiographic features alone an indication for pericardiocentesis, even in the absence of clinical tamponade. The commonest perceived indications for drainage were right ventricular diastolic collapse and right atrial collapse (69% and 33% of respondents respectively). For guidance, 82% use echocardiography, either alone or with fluoroscopy or the electrocardiogram (ECG) injury trace. 11% employ fluoroscopy alone or with the ECG injury trace. The remaining 11% stated that they would use the ECG injury trace alone or use no guidance. Using the ECG injury trace alone is said by the European Society of Cardiology (ESC) guidelines to offer an inadequate safeguard. Reported complications included ventricular puncture (n = 12, 0.8%) and hepatic damage (n = 4, 0.3%). CONCLUSION: Pericardiocentesis practice varies substantially in the UK. Many cardiologists would perform pericardiocentesis based on echocardiographic features alone. 11% of cardiologists use guidance that is considered inadequate by the ESC guidelines.

Prevalence and prognostic implications of electrocardiographic left ventricular hypertrophy in heart failure: evidence from the CHARM programme.

BACKGROUND: Electrocardiographic left ventricular hypertrophy (ECG LVH) is a powerful independent predictor of cardiovascular morbidity and mortality in hypertension. OBJECTIVE: To determine the contemporary prevalence and prognostic implications of ECG LVH in a broad spectrum of patients with heart failure with and without reduced left ventricular ejection fraction (LVEF). METHODS AND OUTCOME: The Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) programme randomised 7599 patients with symptomatic heart failure to receive candesartan or placebo. The primary outcome comprised cardiovascular death or hospital admission for worsening heart failure. The relative risk (RR) conveyed by ECG LVH compared with a normal ECG was examined in a Cox model, adjusting for as many as 31 covariates of prognostic importance. RESULTS: The prevalence of ECG LVH was similar in all three CHARM trials (Alternative, 15.4%; Added, 17.1%; Preserved, 14.7%; Overall, 15.7%) despite a more frequent history of hypertension in CHARM-Preserved. ECG LVH was an independent predictor of worse prognosis in CHARM-Overall. RR for the primary outcome was 1.27 (95% confidence interval (CI) 1.04 to 1.55, p = 0.018). The risk of secondary end points was also increased: cardiovascular death, 1.50 (95% CI 1.13 to 1.99, p = 0.005); hospitalisation due to heart failure, 1.19 (95% CI 0.94 to 1.50, p = 0.148); and composite major cardiovascular events, 1.35 (95% CI 1.12 to 1.62, p = 0.002). CONCLUSION: ECG LVH is similarly prevalent in patients with symptomatic heart failure regardless of LVEF. The simple clinical finding of ECG LVH was an independent predictor of a worse clinical outcome in a broad spectrum of patients with heart failure receiving extensive contemporary treatment. Candesartan had similar benefits in patients with and without ECG LVH.

Potential aluminium toxicity in infants fed special infant formula.

Aluminium was measured in samples of plasma and samples of feed obtained from 74 infants with normal renal function established on various feeds (breast, whey-based, fortified whey-based, preterm, soy, and casein hydrolysate). All infants were bolus fed, and blood samples were collected midway between feeds. Aluminium was measured using electrothermal atomization and atomic absorption spectrometry. Mean aluminium concentrations in milks were as follows: breast, 9.2 micrograms/L [95% confidence interval (CI), 5.6-12.7]; whey-based, 165 micrograms/L (95% CI, 151-180); fortified, 161 micrograms/L (95% CI, 143-180); preterm, 300 micrograms/L (95% CI, 272-328); soy, 534 micrograms/L (95% CI, 470-598); casein hydrolysate, 773 micrograms/L (95% CI, 632-914). Mean plasma aluminium concentrations in infants receiving different milks were as follows: breast, 8.6 micrograms/L (95% CI, 5.6-10.6); whey-based, 9.2 micrograms/L (95% CI, 7.4-11.0); fortified, 10.3 micrograms/L (95% CI, 8.3-12.3); preterm, 9.7 micrograms/L (95% CI, 5.3-17.1); soy, 12.5 micrograms/L (95% CI, 5.0-20.0); casein hydrolysate, 15.2 micrograms/L (95% CI, 10.7-19.8). Mean plasma aluminium concentration was significantly different in infants fed casein hydrolysate formulae than in those fed breast milk (difference, 6.7 micrograms/L; 95% CI, 2.8-10.5; p = 0.028). We conclude that infants may be at risk from aluminium toxicity when consuming formula containing > 300 micrograms/L--in particular, casein hydrolysate formulae. We speculate that the aluminium compounds found in breast milk are more bioavailable than those found in other milks and that some constituents of infant formula affect aluminium absorption from the gut lumen.