Wilma Rademacher

Percutaneous caval stent valve implantation: investigation of an interventional approach for treatment of tricuspid regurgitation

AIMS Severe tricuspid regurgitation (TR) reduces cardiac output (CO) and increases central venous pressure leading to secondary organ dysfunction. To date, the open surgical approach is the only option to treat TR. Herein, we report our experience of treatment by percutaneous implantation of valved stents in the inferior vena cava (IVC) and superior vena cava (SVC) to substitute tricuspid valve function in a model of acute insufficiency. METHODS AND RESULTS Acute TR grades III-IV was created in 13 sheep (54-75 kg) via papillary muscle and chordae avulsion using a 0.07 inch wire blade. Successful creation of TR was confirmed using angiography and by a prominent ventricular wave in central venous pressure recording. Two self-expanding nitinol stents containing a porcine pulmonary valve were then implanted in the IVC and SVC in a transcatheter approach. Implantation was performed through the right jugular vein by means of a 21 F catheter and guided by fluoroscopy. Haemodynamics were continuously monitored and valve function was verified by angiography and epicardial echocardiography. After successful implantation and proof of concept in the acute study (acute group, n = 9), chronic studies were (n = 4, 4 weeks follow-up) performed. Tricuspid regurgitation grades III-IV was successfully created in all animals and resulted in a significant reduction of CO. A ventricular wave in the IVC of 16.2 +/- 2.33 mmHg (acute group) and 14.9 +/- 1.71 mmHg (chronic group) confirmed the presence of severe TR. After deployment of the IVC and the SVC valve, the ventricular wave in the IVC significantly decreased to 13.9 +/- 2.97 mmHg (acute group) and 12.7 +/- 1.15 (chronic group), whereas CO significantly increased to 4.20 +/- 0.84 L/min (acute group) and 5.4 +/- 0.67 L/min (chronic group). At autopsy, correct device position was verified in all successfully implanted animals, no macroscopic damage resulting from the implantation procedure was observed. CONCLUSION In high-grade tricuspid insufficiency, percutaneous implantation of valved stents in the central venous position reduces venous regurgitation and improves haemodynamics in the animal experiment. Implantation of one or two valves in central venous position is technically feasible. Functional replacement of the insufficient tricuspid valve leads to an increase in CO. This technique expands the potential therapeutic options for patients with relevant tricuspid valve regurgitation having a high risk for open heart surgery.

Multidimensional ECG-based analysis of cardiac autonomic regulation predicts early AF recurrence after electrical cardioversion.

BACKGROUND Heart rate turbulence, deceleration capacity (DC), and symbolic dynamics (SD) are promising novel domains of autonomic indices representing the multidimensional qualities of autonomic heart rate dynamics. PURPOSE The aim of this study was to test the impact of these novel indices in predicting early AF recurrence within the first month after electrical cardioversion (CV). METHODS In 45 patients with AF, standard Holter recordings were commenced immediately after CV. Holter-based indices were retrospectively analyzed using computerized algorithms. The best indices were applied in a multivariate model to select the optimal combination set that correctly classified patients who developed early AF recurrence. RESULTS Early AF recurrence occurred in 25 vs 20 patients with stable sinus rhythm. The set with the highest predictive power consisted of DC, turbulence onset, VLF/P, and PTH19 as a parameter of SD. The receiver operating curve analysis applied to this optimum set produced an area under the curve of 0.86, thus correctly classifying patients with 95.0% specificity and 76.0% sensitivity. CONCLUSION The analysis of novel multidimensional Holter-based autonomic indices after CV appears of clinical value because the procedure identifies patients with high risk of early AF recurrence. Furthermore, it indicates a substantial alteration of autonomic regulation.

Heterotopic valve replacement as an interventional approach to tricuspid regurgitation.

To the Editor: Tricuspid regurgitation (TR) is common in patients with late-stage myocardial and valvular heart disease. Severe TR leads to a decrease in cardiac output (CO), and significant symptoms of right heart failure develop, such as peripheral edema and congestive hepatosplenomegaly.

Effect of mechanical ventilation on microvascular perfusion in critical care patients.

PURPOSE Microvascular perfusion, pivotal for adequate tissue oxygenation is potentially linked to outcome in critical care therapy. Mechanical ventilation (MV) and positive end-expiratory pressure (PEEP) as standard concepts of respiratory management are known to have deleterious effects on regional organ perfusion especially in the splanchnic area. As these effects have been attributed to different physiologic mechanisms, the purpose of this study was to investigate the effect of positive pressure ventilation on extra-abdominal tissue perfusion in non-surgical intensive care patients. METHODS Sublingual microcirculation was evaluated in 46 severely ill patients (group 1: n=26 requiring MV and PEEP; group 2: n=20 spontaneous breathing) admitted to the intensive care unit using sidestream darkfield intravitalmicroscopy. According to current guidelines, sublingual vessels were categorized by means of size and flow in semi-quantitative categories determining microvascular flow index (MFI). Total microvascular flow index (TMFI) was calculated for each patient as mean value of flow in all vessel categories. RESULTS No significant difference was observed between both groups in microvascular flow index in each vessel category and in total microvascular flow index. Patients requiring mechanical ventilation presented with more comorbidities and higher acuity of illness scores resulting in a higher ICU mortality, which however was not accompanied by microcirculatory differences at the time of measurement. CONCLUSION Mechanical ventilation and PEEP have no general deleterious effects on microvascular perfusion of the sublingual mucosa. However, further clinical studies are required to investigate potential effects of higher levels of ventilation pressure or PEEP on microvascular perfusion.

Acute and long-term outcome of unprotected left main coronary angioplasty compared to the anticipated surgical risk

OBJECTIVES Percutaneous coronary intervention of unprotected left main (ULM) stenosis is increasing despite surgical revascularisation being the recommended treatment by the current guidelines. We compared the 30-day and 9-month mortality after ULM stenting with the predicted surgical outcome as determined by the EuroSCORE. METHODS AND RESULTS We included 81 consecutive patients who underwent ULM stenting. The patient cohort was divided into a normal risk group (EuroSCORE <or=5, predicted 30-day mortality <3%), and a high-risk group (EuroSCORE >5, predicted 30-day mortality 11%). Follow-up examinations were scheduled for one and nine months after the initial PCI. The average EuroSCOREs in the normal- and high-risk group were 3.0 (29 patients, 36%) and 10.0 (52 patients, 64%), respectively. Mortality rates at 30 days were 3% in the normal-risk group and 8% in the high-risk group. Subacute stent thrombosis occurred in 3.4% (three patients) undergoing elective PCI. Major adverse cardiac events during the nine months follow-up were registered in 24% of patients in the normal-risk group, and in 27% of the patients in the high-risk group. CONCLUSION Short-term outcome of ULM stenting in our high-risk patients is comparable to surgical outcome predicted by the EuroSCORE. Long-term outcome was less favourable due to a high mortality rate. ULM stenting in patients with low surgical risk could be associated with higher mortality rates compared to CABG because of the unpredictable risk of a fatal stent thrombosis.

Postpartum unmasking of a severe triple-vessel-disease with acute myocardial infarction

Myocarditis as well as acute myocardial infarction may both present with similar clinical, laboratory, electrocardiographic and echocardiographic abnormalities making it difficult to discriminate between the two conditions. Diagnosis of heart disease during pregnancy is even more challenging due to restraints on diagnostic procedures associated with radiation exposure or administration of drugs and contrast agents. Herein, we report the fateful course of a pregnant woman with severe coronary artery disease (CAD) mimicking viral myocarditis.

Erratum to: Impact of rapid ventricular pacing during TAVI on microvascular tissue perfusion

Patient characteristics Age (years ± SD) 81.21 ± 8.44 Male, n (%) 18/26 AVA (cm ± SD) 0.64 ± 0.17 cm Vmax (m/s ± SD) 4.58 ± 0.66 m/s Mean pressure gradient (mmHg ± SD) 48.79 ± 16.73 mmHg Ejection fraction (EF ± SD) 55.93 ± 15.89 % log EuroScore 28.89 ± 14.07 Comorbidities Arterial hypertension n (%) 42 (100) CAD n (%) 32 (76.2) Diabetes mellitus n (%) 19 (45.2) Atrial fibrillation n (%) 11 (26.2) Renal insufficiency n (%) 10 (23.8) Peripheral vascular disease n (%) 9 (21.4) Previous myocardial infarction n (%) 7 (16.67) Pulmonary hypertension n (%) 5 (11.9) Previous stroke n (%) 3 (7.14)