The data extraction and longitudinal trend analysis network study of distributed automated postmarket cardiovascular device safety surveillance.

BACKGROUND: Current approaches for postmarket medical device safety surveillance are limited in their ability to produce timely and accurate assessments of adverse event rates. METHODS AND RESULTS: The Data Extraction and Longitudinal Trend Analysis (DELTA) network study was a multicenter prospective observational study designed to evaluate the safety of devices used during percutaneous coronary interventions. All adult patients undergoing percutaneous coronary intervention from January 2008 to December 2012 at 5 participating Massachusetts sites were included. A safety alert was triggered if the cumulative observed adverse event rates for the study device exceeded the upper 95% confidence interval of the event rates of propensity-matched control cohort. Prespecified sensitivity analyses were developed to validate any identified safety signal. A total of 23,805 consecutive percutaneous coronary intervention procedures were evaluated. Two of 24 safety analyses triggered safety alerts. Patients receiving Perclose vascular closure device experienced an increased risk of minor vascular complications (relative risk, 4.14; P<0.01) and any vascular complication (relative risk, 2.06; P=0.01) when compared with propensity-matched patients receiving alternative vascular closure device, a result primarily driven by relatively high event rates at 1 participating center. Sensitivity analyses based on alternative risk adjustment methods confirmed a pattern of increased rate of complications at 1 of the 5 participating sites in their use of Perclose vascular closure device. CONCLUSIONS: The DELTA network study demonstrates that distributed automated prospective safety surveillance has the potential of providing near real-time assessment of safety risks of newly approved medical devices.

Structural and functional uncoupling of liver performance in the Fontan circulation.

BACKGROUND: The liver is known to be structurally abnormal in long-standing Fontan circulation. The degree of liver dysfunction associated with such abnormalities is however largely unknown. We assessed structural changes (serum fibrosis markers) and function (indocyanine green clearance (ICG)) in Fontan patients. METHODS: 21 stable Fontan patients were prospectively assessed and compared with 8 histologically proven compensated viral cirrhotic patients. All subjects had standard liver profile, "Enhanced Liver Fibrosis" (ELF) score (including hyaluronic acid, aminoterminal type III procollagen peptide P3NP and tissue inhibitor of metalloproteinase TIMP-1 levels), and ICG using the LiMON Device. Plasma disappearance rate (PDR) and 15-minute retention (R15) were recorded after ICG infusion. RESULTS: Indocyanine clearance and retention (PDR and R15) were similar between Fontan and compensated cirrhotic patients (17 ± 5 vs 18 ± 6 (p=0.75) and 11 ± 10 vs 10 ± 10 (p=0.75)), as was degree of fibrosis (7.97 ± 1.16 vs 9.0 ± 1.43, p=NS). There was a positive correlation between PDR and ELF (R=0.77, p=0.028) as well as R15 and ELF (R=0.905, p=0.002) in the viral cirrhotics but not in the Fontan group. (R=-0.243, p=0.302; and R=0.226, p=0.338). PDR (17 ± 5) and R15 (11 ± 10) were not significantly different in Fontan as compared with the established cirrhotics. CONCLUSIONS: Fontan patients have similar global hepatic function and fibrosis as compared with viral cirrhotic patients. However in Fontan patients, fibrosis was not closely correlated with global liver function, whereas viral cirrhotic patients exhibited a close correlation between function and fibrosis.

Arterialised hepatic nodules in the Fontan circulation: hepatico-cardiac interactions.

Hypervascular nodules occur commonly when there is hepatic venous outlet obstruction. Their nature and determinants in the Fontan circulation is poorly understood. We reviewed the records of 27 consecutive Fontan patients who had computerized tomography scan (CT) over a 4 year period for arterialised nodules and alterations in hepatic flow patterns during contrast enhanced CT scans and related these findings to cardiac characteristics. Mean patient age was 24 ± 5.8 years, (range 16.7-39.8) and mean Fontan duration was 16.8 ± 4.8 years (range 7.3-28.7). Twenty-two patients demonstrated a reticular pattern of enhancement, 4 a zonal pattern and only 1 demonstrated normal enhancement pattern. Seven (26%) patients had a median of 4 (range 1-22) arterialised nodules, mean size 1.8 cm (range 0.5 to 3.2 cm). All nodules were located in the liver periphery, their outer aspect lying within 2 cm of the liver margin. Patients with nodules had higher mean RA pressures (18 mmHg ± 5.6 vs. 13 mmHg ± 4, p=0.025), whereas their mixed venous saturation and aortic saturation was not significantly different (70% ± 11 vs. 67% ± 9 and 92% ± 10 vs. 94% ± 4, p>0.05). Post-mortem histology suggests focal nodular hyperplasia is the underlying pathology. ConclusionsAbnormalities of hepatic blood flow and the presence of arterialised nodules are common in the failing Fontan circulation. They occur especially when central venous pressures are high, and very likely indicate arterialisation of hepatic blood flow and reciprocal portal venous deprivation. The underlying pathology is most likely focal nodular hyperplasia.

Renal function of patients with a failing Fontan circuit undergoing total cavopulmonary revision surgery.

This report characterizes renal dysfunction after total cavopulmonary (TCPC) revision surgery for atriopulmonary Fontan (APF) circulations, a known risk factor for a poor outcome. The perioperative data for 23 consecutively identified patients were reviewed. The preoperative mean glomerular filtration rate (GFR) was 101 +/- 30 ml/min/1.73 m(2), decreasing to 65 +/- 41 ml/min/1.73 m(2) early in the postoperative period. The preoperative GFR was highly correlated with age at APF (r = -0.5; p = 0.024), age at TCPC (r = -0.5; p = 0.01), and mixed venous saturation (r = 0.6; p = 0.01). Three of four patients requiring renal replacement therapy (RRT) died at a median age of 3 months (range, 18 days to 9 months). Determinants of early GFR and RRT were preoperative GFR (p = 0.016) and creatinine (p = 0.035). Younger age at primary Fontan (p = 0.008), higher preoperative mixed venous saturation (p = 0.019), and higher preoperative blood pressure (p = 0.006) independently predicted better GFRs at the latest follow-up evaluation. Renal function declines acutely after TCPC revision, often necessitating RRT. A requirement for RRT marks greater mortality. Higher preoperative creatinine levels identify those at greatest risk.

Hepatic changes in the failing Fontan circulation.

BACKGROUND: The failing Fontan circulation is associated with hepatic impairment. The nature of this liver injury is poorly defined. OBJECTIVE: To establish the gross and histological liver changes of patients with Fontan circulation relative to clinical, biochemical and haemodynamic findings. METHODS: Patients were retrospectively assessed for extracardiac Fontan conversion between September 2003 and June 2005, according to an established clinical protocol. Twelve patients, mean age 24.6 (range 15.8-43.4) years were identified. The mean duration since the initial Fontan procedure was 14.1 (range 6.9-26.4) years. RESULTS: Zonal enhancement of the liver (4/12) on CT was more common in patients with lower hepatic vein pressures (p = 0.007), and in those with absent cardiac cirrhosis on histological examination (p = 0.033). Gastro-oesophageal varices (4/12) were more common in patients with higher hepatic vein pressure (21 (6.3) vs 12.2 (2.2) mm Hg, p = 0.013) and associated with more advanced cirrhosis (p = 0.037). The extent of cirrhosis (7/12) was positively correlated with the hepatic vein pressure (r = 0.83, p = 0.003). A significant positive correlation was found between the Fontan duration and the degree of hepatic fibrosis (r = 0.75, p = 0.013), as well as presence of broad scars (r = 0.71, p = 0.021). Protein-losing enteropathy (5/12) occurred more frequently in patients with longer Fontan duration (11.7 (3.2) vs 17.9 (6.1) years, p = 0.038). CONCLUSIONS: Liver injury, which can be extensive in this patient group, is related to Fontan duration and hepatic vein pressures. CT scan assists non-invasive assessment. Cardiac cirrhosis with the risk of developing gastro-oesophageal varices and regenerative liver nodules, a precursor to hepatocellular carcinoma, is common in this patient group.

Esmolol-assisted balloon and stent angioplasty for aortic coarctation.

The objective of this study was to evaluate the effectiveness and safety of esmolol-induced negative ino- and chronotropism during stent/balloon angioplasty for aortic coarctation. Balloon angioplasty and stent placement have become widely accepted therapies for native and recurrent coarctation of the aorta (CoA). Trauma to the vessel wall and stent migration related to forward displacement of the balloon and/or stent by cardiac output, are the most common complications. Controlling stroke volume and heart rate may assist in balloon stability and accurate deployment of stents. All methods currently used to achieve this have significant limitations. We describe our experience using esmolol to control stroke volume and heart rate during balloon/stent angioplasty of CoA. We performed a retrospective review of all patients who had intravenous esmolol during percutaneous treatment of CoA. Six interventions were performed in six patients: coarctation stent angioplasty in five patients (two native coarctation) and balloon angioplasty alone in one patient. The median systolic blood pressure achieved during the procedure was 65 mmHg (range, 57-75) representing a median reduction of 40 mmHg (range, 20-80; p = 0.008) from baseline. The median heart achieved was 50 beats/min (range, 20-80), representing a median reduction of 20 beats/min (range, 15-90, p = 0.048) from baseline. Optimal stent position was obtained in all patients. Intravenous esmolol controls periprocedural hemodynamics effectively and safely during percutaneous therapy for aortic coarctation, thereby aiding accurate stent placement. Further evaluation of its use during other percutaneous left heart interventions is required.