Transcatheter interventions of coarctation of the aorta (CoA): a multinational population-based registry – procedural complications

Background

Patients with a native or re CoA with an invasively meassured peak to peak gardient >20 mmHg have a guideline indication for intervention. The decision regarding transcatheter versus surgical intervention depends on a variety of factors including location and complexity of CoA, patient/parent preference and availability of a team capable to perform the intevention with a low rate of complications. The aim of the present analysis was to describe factors associated with risk for procedural complications during transcatheter interventions in CoA. Separate anlysis was done for complications at intervention site and at access site.

Methods

All consecutive patients undergoing catheter interventions for CoA from 1st of January 2000 to 31st of December 2016 were identified by each of the particpating nine centers. The nine centers perform all catheter interventions for CoA for a complete population coverage of 25 millions inhabitants. A common protocol was filled out from medical records. Exclusion criteria were weight less than 20 kg at the time of intervention or Norwood surgery for hypoplastic left heart surgery. Complications at the intervention site included aneurysm formation, dissection of the aorta, extravasation of the aorta or neurological impairment. Complications at the access site was defined as any complication that prolonged the hospital stay.

Results

590 interventions were performed on 520 patients: two interventions n=76, three: n=11, four n=2 and one patient underwent five interventions. There was no mortality in relation to the procedure or during the hospitalisation. The age span of the patients was wide; 4–79 years old (median= 23). 51% had a native CoA, 42% post surgery re-CoA, 22% had had a previous catheter intervention. In 160 (27%) of the interventions balloon dilatation only was performed. Overall, procedural succes was 87%, n=513, 44 procedures (8%) were partially successful and 9 procedures (2%) were not successful. 512 (87%) had one day in hospital stay and 17 patients (6%) had a hospital stay longer than 3 days. In 11 procedures (1.9%) at least one complication occurred at the intervention site; (6 aneurysm formation, 3 neurological impairment, 3 dissection of aorta, 2 extra vasation of aorta), nine of them without prolonged hospital stay. In 25 procedures (4.2%) at least one complications at the access site was observed. Access site complications were associated with older age (mean 38 years (10–79))

Conclusions

In a large, multicenter registry with complete follow-up, complications at the intervention site occurred in 1.9% and at the access site in 4.2% of interventions. Transcatheter intervention of CoA can be performed with low risk of complications.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): ALF-LUA, Gothenburg Heart and Lung Foundation

Transcatheter intervention of coarctation of the aorta (CoA): a multinational population-based registry – effect on hypertension

Background

CoA is associated with hypertension caused by reduced wind kessel function in the aortic arch, general hypoplasia of the arch and/or essential hypertension. In patients with a native or recurrent/rest CoA, a gradient >20 mmHg by non-invasive meassurement if associated with hypertension is an ESCguideline indication for intervention. We studied the persistence and presence of hypertension after transcatheter intervention of a CoA

Methods

All consecutive patients undergoing catheter interventions for CoA from 1st of January 2000 to 31st of December 2016 were identified by each of the particpating nine centers. The nine centers perform all catheter interventions for CoA for a complete population coverage of 25 millions inhabitants. A common protocoll was filled out from medical records. Hypertension was defined as a pre-intervention blood pressure above 140/80 or pharmacological treatment of hypertension. Exclusion criteria were weight less than 20 kg at the time of intervention or Norwood surgery

Results

590 interventions were performed on 520 patients: two interventions n=76, three: n=11, four n=2 and one patient underwent five interventions. Before intervention, 437 (74%) of the patients were hypertensive and 285 were on pharmacologocal treatment; 134 (48%) were treated with one drug, 79 patients (28%) with two drugs, 41 patients (15%) with three drugs and 14 (5%) with four drugs. After the intervention during follow up hypertension was present in 294 patients (50%, p<0.001 vs pre) of whom 270 (46%) were on pharmacological treatment; with one drug, n=128 (48%), two drugs n=93 (34%), three drugs n=34 (13%) or 4 drugs n=7 (3%).

Conclusions

Catheter intervention of CoA reduced the presence of hypertension significantly from 74% down to 50% but many patients will remain hypertensive and in need for treatment. Life time follow up also after transcatheter CoA intervention seems warranted.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): ALF-LUA, Heart and Lung Foundation

The endothelin receptor antagonist bosentan improves peripheral endothelial function in patients with type 2 diabetes mellitus and microalbuminuria: a randomised trial

AIMS/HYPOTHESIS

Endothelial dysfunction is important in the development of vascular complications in diabetes. Patients with type 2 diabetes have increased production of the vasoconstrictor and pro-inflammatory peptide, endothelin-1. Short-term intra-arterial administration of endothelin antagonists improves endothelium-dependent vasodilatation in patients with type 2 diabetes. We tested the hypothesis that oral administration of the dual endothelin receptor antagonist, bosentan, improves peripheral endothelial function in patients with type 2 diabetes and microalbuminuria.

METHODS

This placebo-controlled and double-blind study was performed on 46 patients with type 2 diabetes and microalbuminuria (urine albumin/creatinine ratio >3 mg/mmol) at a medical university department. Patients were randomised to bosentan, 125 mg two times per day (n = 28), or placebo (n = 28) for 4 weeks. The computer-generated randomisation code was kept in sealed envelopes. Patients and people doing examinations or assessing outcomes were blinded. The primary endpoint was change in microvascular endothelium-dependent vasodilatation, based on change in digital reactive hyperaemia index. The secondary endpoint was change in brachial artery flow-mediated vasodilatation.

RESULTS

Reactive hyperaemia index increased from 1.73 ± 0.43 (mean ± SD) at baseline to 2.08 ± 0.59 at follow-up (p < 0.05) in the bosentan group (n = 22), but did not change in the placebo group (1.84 ± 0.49 to 1.87 ± 0.47; n = 24). The change in reactive hyperaemia index from baseline was greater in the bosentan group than in the placebo group (p < 0.05). Nitroglycerine-induced digital hyperaemia was not affected. Brachial artery flow-mediated vasodilatation and blood pressure did not change during treatment.

CONCLUSIONS/INTERPRETATION

Oral treatment of 4 weeks duration with the dual endothelin receptor antagonist, bosentan, improves peripheral endothelial function in patients with type 2 diabetes and microalbuminuria.

Endothelin attenuates endothelium-dependent platelet inhibition in man

AIM

The vascular endothelium produces several substances, including nitric oxide (NO) and endothelin-1 (ET-1), which participate in the regulation of vascular tone in humans. Both these substances may exert other actions of importance for cardiovascular disease, e.g. effects on vascular smooth muscle cell proliferation and inflammation, and NO inhibits platelet function. Experiments were designed to investigate the effect of ET-1 on endothelium-dependent vasodilatation and attenuation of platelet activation.

METHODS

In 25 healthy male subjects (25 +/- 1 years), forearm blood flow was measured by venous occlusion plethysmography, and platelet activity was assessed by whole blood flow cytometry (platelet fibrinogen binding and P-selectin expression) in unstimulated and adenosine diphosphate (ADP)-stimulated samples during administration of ET-1, the endothelium-dependent vasodilator acetylcholine and the NO synthase inhibitor l-NMMA.

RESULTS

Acetylcholine increased forearm blood flow and significantly inhibited platelet activation in both unstimulated and ADP-stimulated samples. In samples stimulated with 0.3 microm ADP, fibrinogen binding decreased from 41 +/- 4% to 31 +/- 3% (P < 0.01, n = 11) after acetylcholine administration. The vasodilator response to acetylcholine was significantly impaired during infusions of ET-1 and l-NMMA. ET-1 did not affect platelet activity per se, whereas l-NMMA increased platelet P-selectin expression. Both ET-1 and l-NMMA attenuated the acetylcholine-induced inhibition of platelet activity.

CONCLUSIONS

Our study indicates that, further to inhibiting endothelium-dependent vasodilatation, ET-1 may also attenuate endothelium-dependent inhibition of platelet activation induced by acetylcholine. An enhanced ET-1 activity, as suggested in endothelial dysfunction, may affect endothelium-dependent platelet modulation and thereby have pathophysiological implications.

L-arginine and tetrahydrobiopterin protects against ischemia/reperfusion-induced endothelial dysfunction in patients with type 2 diabetes mellitus and coronary artery disease

Diminished levels of L-arginine and endothelial nitric oxide synthase (eNOS) uncoupling through deficiency of tetrahydrobiopterin (BH(4)) may contribute to endothelial dysfunction. We investigated the effect of L-arginine and BH(4) administration on ischemia-reperfusion (I/R)-induced endothelial dysfunction in patients with type 2 diabetes and coronary artery disease (CAD). Forearm blood flow was measured by venous occlusion plethysmography in 12 patients with type 2 diabetes or impaired glucose tolerance and CAD. Forearm ischemia was induced for 20 min, followed by 60 min of reperfusion. The patients received a 15 min intra-brachial infusion of L-arginine (20 mg/min) and BH(4) (500 microg/min) or 0.9% saline starting at 15 min of ischemia on two separate study occasions. Compared with pre-ischemia the endothelium-dependent vasodilatation (EDV) induced by acetylcholine was significantly reduced at 15 and 30 min of reperfusion when saline was infused (P<0.001), but not following L-arginine and BH(4) infusion. EDV was also significantly less reduced at 15 and 30 min of reperfusion following L-arginine and BH(4) infusion, compared to saline infusion (P<0.02). Endothelium-independent vasodilatation (EIDV) induced by nitroprusside was unaffected by I/R. Venous total biopterin levels in the infused arm increased from 37+/-7 at baseline to 6644+/-1240 nmol/l during infusion of L-arginine and BH(4) (P<0.0001), whereas there was no difference in biopterin levels during saline infusion. In conclusion L-arginine and BH(4) supplementation reduces I/R-induced endothelial dysfunction, a finding which may represent a novel treatment strategy to limit I/R injury in patients with type 2 diabetes and CAD.