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BACKGROUND: The aim of the study was to compare the detection of clinically significant coronary artery stenosis using a magnetic resonance 3-dimensional (3D) breath-hold true fast imaging with steady-state precession (trueFISP) sequence with conventional coronary angiography. METHODS: Twenty-nine patients who were scheduled to undergo or had recently undergone diagnostic conventional coronary angiogram participated in this study. The left main, left anterior descending, left circumflex, and right coronary arteries were studied using the 3D breath-hold trueFISP technique. Each artery was imaged with 1 acquisition in 16 to 32 heartbeats. The image quality, vessel length, and presence or absence of stenosis were evaluated. A score of 1 to 3 (1 = noninterpretable, 2 = good, 3 = excellent) was used to assess image quality. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of magnetic resonance angiography in detecting significant coronary artery stenosis (> 50% luminal narrowing) on conventional coronary angiogram were calculated. RESULTS: Of 116 vessels, 108 were assessed in 29 patients. Twenty vessels that had image quality score of 1 were excluded from further evaluation. The mean lengths of vessels visualized were the following: left anterior descending 3.6 cm, left circumflex 3.4 cm, and right coronary 6.6 cm. The entire length of the left main coronary artery was visualized. For the visualized arterial segments, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for detecting significant coronary artery stenosis were 92.8%, 95.3%, 95.0%, 68.4%, and 99.2%, respectively. CONCLUSIONS: The 3D breath-hold trueFISP technique, which uses the endogenous contrast of blood, is potentially useful in ruling out significant coronary artery stenosis but not yet sensitive enough as a screening tool.

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BACKGROUND: Left ventricular hypertrophy (LVH) and dialysis adequacy are both important predictors for mortality in dialysis patients. This study evaluated the association between residual renal function (RRF) and the severity of LVH in endstage renal failure (ESRF) patients undergoing long-term continuous ambulatory peritoneal dialysis (CAPD). METHODS: A cross-section study was performed with left ventricular mass index (LVMi), determined in 158 non-diabetic CAPD patients using echocardiography and its relationship with residual glomerular filtration rate (GFR), peritoneal dialysis (PD) and total weekly urea clearance (Kt/V) and other known risk factors for LVH was evaluated. RESULTS: Twelve patients had no LVH (group I). The remaining 146 patients were stratified [group II (lowest), III and IV (highest)] according to the LVMi (median 207 g/m2; range 103 to 512 g/m2). Across the four groups of patients with increasing LVMi, there was significant decline in GFR (2.27 +/- 1.98 vs. 1.49 +/- 1.58 vs. 1.61 +/- 1.91 vs. 0.80 +/- 1.42 mL/min/1.73 m2; P = 0.011) and total weekly Kt/V (1.98 +/- 0.44 vs. 1.96 +/- 0.38 vs. 1.92 +/- 0.42 vs. 1.71 +/- 0.42; P = 0.037); however, PD Kt/V was similar for all four groups. Patients with better-preserved residual GFR not only had significantly higher total Kt/V, but were less anemic and hypoalbuminemic and had a trend toward lower systolic blood pressure and arterial pulse pressure. Multiple regression analysis showed that other than age, gender, body weight, arterial pulse pressure, hemoglobin and serum albumin, known factors for LVH, residual GFR (estimated mean -7.94; 95% confidence interval -15.13 to -0.74; P = 0.031) was also independently associated with LVMi. CONCLUSIONS: Other than anemia, hypoalbuminemia and arterial pulse pressure, this study demonstrates an important, novel association between the degree of RRF and severity of LVH in ESRF patients undergoing long-term CAPD. Prospective studies are needed to define if indeed there is a cause-effect relationship between this association, to evaluate if a decline in residual GFR is independently associated with an increase in LVMi, and to determine whether treatment directed at preserving RRF will reduce the severity of LVH, improve cardiac performance and hence survival of these patients.

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Cardiac valve calcification (VC) has long been regarded as a consequence of aging and abnormal calcium-phosphate metabolism in uremic patients. In view of the recent recognition of association among inflammation, malnutrition, and atherosclerosis, the possible role of inflammation and malnutrition in VC was investigated. Inflammatory markers (including C-reactive protein [CRP], fibrinogen, and basal metabolic rate) and nutritional status (assessed using serum albumin, subjective global nutrition assessment, and handgrip strength) were examined, in addition to calcium phosphate parameters and other traditional cardiovascular risk factors, including gender, smoking habits, BP, and lipid profile, in relation to VC in 137 patients who were on continuous ambulatory peritoneal dialysis. Compared with patients with no VC, patients with VC not only were older (60 [10] versus 54 [12] yr; P = 0.005), had higher plasma phosphate (1.89 [0.52] versus 1.64 [0.41] mmol/L; P = 0.003), and had higher parathyroid hormone (83 [40, 145] versus 38 [16, 71] pmol/L; P = 0.001) but also had higher CRP (4.5 [0.1, 13.4] versus 0.2 [0.1, 4.4] mg/L; P = 0.004), had higher fibrinogen (6.6 [1.9] versus 5.7 [1.3] g/L; P = 0.002), and had lower serum albumin (26 [4] versus 29 [3] g/L; P = 0004). Twenty-three percent of patients with VC versus 17% of patients with no VC were moderately to severely malnourished according to subjective global nutrition assessment (P = 0.05). Even after adjustment for patients' age, duration of continuous ambulatory peritoneal dialysis, diabetes, and calcium x phosphate product, cardiac VC remained strongly associated with CRP (odds ratio, 1.05; P = 0.026) and albumin (odds ratio, 0.85; P = 0.01). The data suggest that VC not only is a passive degenerative process but also involves active inflammation, similar to that seen in atherosclerosis. The presence of uncontrolled hyperphosphatemia and hyperparathyroidism further accelerates the progression of calcification. The data also indicate that VC and atherosclerosis should be considered as associated syndromes, sharing similar pathogenic mechanisms, namely active inflammation.

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