Transcatheter closure of patent foramen ovale using the Cocoon occluder: A multicenter retrospective study

BACKGROUND

The Cocoon patent foramen ovale (PFO) occluder is a new device especially designed for transcatheter closure of PFO. This occluder has some distinctive structural modifications aimed at reducing the risk of major complications of transcatheter PFO closure. In this report we present our initial experience to evaluate the efficacy and safety of the Cocoon PFO occluder in 253 patients who underwent transcatheter PFO closure.

METHODS

The study cohort included 253 patients (median age 45 years) with embolic stroke of undetermined source who underwent attempted transcatheter closure of PFO for secondary prevention of paradoxical embolism. Patients were enrolled retrospectively from five sites in Greece and one in Romania between December 2016 and January 2021, and the median follow-up period was 28 months (range 12-48 months). Clinical and laboratory data from each participating center were sent to an electronic registry for evaluation and statistical analysis.

RESULTS

The Cocoon PFO occluder was permanently implanted in all patients. At 6 months, complete occlusion of PFO was observed in 251/253 (99.2%) patients. Three (1.2%) patients had a trivial residual shunt. Thrombus formation on the device, which was successfully treated with recombinant tissue plasminogen activator infusion, was observed in one (0.4%) patient. No other complications occurred. During a median follow-up period of 28 months, 3 (1.2%) patients, aged 64-67 years, developed new onset paroxysmal atrial fibrillation. No neurologic events, cardiac erosions, allergic reactions to nickel, or thrombus formation occurred.

CONCLUSION

The Cocoon PFO occluder is an effective and safe device that adds to our armamentarium for transcatheter closure of PFO.

Left Distal Radial Artery Access for Coronary Angiography and Interventions: A 12-Month All-Comers Study

BACKGROUND

Interventional cardiologists prefer the right radial artery (RA) approach for coronary angiography and interventions, mainly for ergonomic reasons. However, the use of the left RA presents certain advantages, and the snuffbox approach has further potential advantages, including lower probability for RA occlusion, avoidance of direct puncture of the RA (thus maintaining its suitability for use as a graft), as well as easier and faster hemostasis.

METHODS

Consecutive patients scheduled for coronary catheterization were included, using the left distal RA (ldRA) in the anatomical snuffbox as the default vascular access site.

RESULTS

Out of 2034 consecutive cases, the ldRA was used as initial vascular access in 1977 patients (97.2%). The procedural failure rate was 9.9% (21.9% inability to puncture the artery, 75.0% inability to advance the wire, 3.1% other reasons). There was a sharp decrease in failure rate after about the first 200 cases (20.8% in the first decile vs 8.7% throughout the rest of the caseload; P<.001). No or very weak palpable pulse was the most important predictor of failure (odds ratio, 16.0; 95% confidence interval, 11.2-23.1; P<.001), in addition to older age, small stature, and female gender (although, after adjustment for height, the latter was no longer significant).

CONCLUSION

In a large series of consecutive patients scheduled for left heart catheterization, through a period of 12 months, with virtually no exclusions except those few imposed by anatomy or compelling clinical needs, the ldRA arterial access approach was shown to be highly effective, feasible, and safe.

International experience with the use of Cocoon septal occluder for closure of atrial septal defects

BACKGROUND

The Cocoon septal occluder (CSO) is a new generation double disk occluder device for catheter closure of the secundum atrial septal defect (ASD). Initial clinical evaluations with the use of this device have shown quite satisfactory results but large follow-up studies are missing. In this international multicenter study, we present procedural and follow-up data from 4008 patients with secundum ASD who underwent catheter closure with the use of CSO.

METHODS

The study cohort consisted of 1853 pediatric and 2155 adult patients with secundum ASD treated with the CSO. Patients were enrolled retrospectively from 11 international centers and were followed for a mean period of 43 months (range 12-84 months), postprocedural. Clinical, electrocardiographic, echocardiographic, procedural, and follow-up data were collected from each collaborating hospital.

RESULTS

The CSO was permanently implanted in 3983 patients (99.4%). Echocardiographic evaluation at one month follow-up revealed complete closure in 99.6% of those patients who had a device implanted. Thrombus formation in one adult patient was the only major device related to procedural complication. During the follow-up period, no patient developed cardiac erosions, allergic reactions to nickel, or other major complications.

CONCLUSIONS

Implantation of CSO provided satisfactory procedural and follow-up results with high success and no device-related cardiac erosions and nickel allergy.

Altered Calcium Handling in Reperfusion Injury

Coronary Heart Disease (CHD) is the major mortality cause in the Western Hemisphere. Reinstituting blood flow in the acutely occluded coronary vessel became the standard intervention to prevent Myocardial Infarct (MI) progression. Ever since their conception, thrombolysis, Percutaneous Coronary Intervention (PCI) and Coronary Artery Bypass Grafting (CABG) have been at the forefront of CHD treatment, limiting MI size. However, it quickly became apparent that after a period of ischemia, reperfusion itself sets off a cascade of events leading to cell injury. It seems that cellular changes in the ischemic period, prime the cell for a loss of homeostasis once blood flow returns. Loss of calcium (Ca(2+)) regulation has been found to be a main culprit in both ischemia and reperfusion. Indeed, sarcoplasmic Ca(2+) overload during reperfusion is related to hypercontracture, proteolysis and mitochondrial failure--the so-called Reperfusion Injury (RI). Ca(2+) channels of the sarcolemma (SL) (L-Type Ca((2+)) Channels, Sodium / Calcium Exchanger) initiate Ca(2+) flux and those of the Sarcoplasmic Reticulum (SR) (Ca(2+) ATPase, Ca(2+) release channel) sustain the rise in intracellular Ca(2+) concentration. Ensuing interplay between Ca(2+), SR, mitochondria, myofilaments and proteolytic cascades i.e. calpain activation, results in cell injury. Novel insight about this interplay and details about the extent by which each of these players contributes to the RI, may allow scientists to devise and design proper interventions that ultimately reduce RI in clinical practice. The present article reviews the literature about key subcellular players participating in the sustained rise of cardiac myocyte cytosolic Ca(2+) during ischemia and reperfusion.

Calcium Handling and Arrhythmogenesis

Intracellular calcium homeostasis plays a fundamental role in the electric and mechanical function of the heart by modulating action potential pattern and duration, by linking cell membrane depolarization to myocardial contraction and by regulating cardiac automaticity. Abnormalities of intracellular calcium regulation disrupt the electrophysiological properties of the heart and create an arrhythmogenic milieu, which promotes atrial and ventricular arrhythmogenesis and impairs cardiac automaticity and atrioventricular conduction. In this brief review, we summarize the basic genetic, molecular and electrophysiological mechanisms linking inherited or acquired intracellular Ca(2+) dysregulation to arrhythmogenesis.