Magnetic-guided percutaneous coronary intervention enabled by two-dimensional guidewire steering and three-dimensional virtual angioscopy: initial experiences in daily clinical practice.

AIMS: Percutaneous coronary intervention (PCI) has been broadly established and often includes highly complex stenoses that require difficult navigation. The purpose of this study is to assess the feasibility of a new magnetic navigation system (MNS) to enable intracoronary guidewire deployment and PCI in daily clinical practice and to compare the 2D guidance to the virtual 3D angioscopy feature. METHODS AND RESULTS: We included 30 consecutive patients (pt) in whom 36 coronary arteries were PCI targets. Patients were randomized to guidewire steering by either 2D guidance or virtual 3D angioscopy (33%). In 31/36 (86%) interventions the MNS guidewire successfully passed the culprit stenosis and the procedure was accomplished by PCI. In 5/30 pt an MNS multivessel intervention was performed. Three of 5 unsuccessful procedures failed due to an unsuccessful recanalization of a subtotal chronic occlusion including 1 pt who required surgical intervention. In 2/36 procedures the magnetic guided intervention was performed effectively after prior conventional failure related to complex anatomy. The contrast medium amount needed to position the magnetic guidewire was 60 +/- 101 mL in 2D accomplished interventions vs. 14 +/- 15 mL in 3D procedures (p < 0.05). In 3 pt the MNS did not harm the implanted pacemaker or defibrillator system. CONCLUSION: Magnetic guided PCI is useful in selected patients. In our experience, success is less likely in evidence of a subtotal occlusion.

[Interventional treatment in hypertrophic cardiomyopathy]. / Hypertrophische Kardiomyopathie Myektomie, Schrittmacher, TASH oder ICD?

Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease phenotypically expressed in the general population at about 0.2%. Annual mortality rate is about 1% in unselected patients, 3-6% in patients with severe symptoms, and 17% following resuscitation from ventricular tachycardia (VT)/ventricular fibrillation (VF). 50-80% of deaths are sudden. Beneath effective treatment in severe symptoms of heart failure (most common in midlife and beyond) the prevention of sudden death (most common in young patients) continues to be a major challenge. The highest risk has been associated with any of the following markers: 1. prior cardiac arrest or spontaneous sustained VTs, 2. a family history of premature HCM-related death, 3. extreme left ventricular hypertrophy (> or = 30 mm), 4. syncope, 5. multiple bursts of nonsustained VTs, 6. hypotensive blood pressure response to exercise, and 7. marked septal scarring (hyperenhancement in magnetic resonance imaging). Treatment options in patients with drug-refractory symptoms or increased risk of sudden death are surgical myectomy, transcoronary ablation of septal hypertrophy (TASH), dual-chamber pacing, ablation of atrial fibrillation (or the AV node), and the implantable cardioverter defibrillator (ICD). 1. Surgical myectomy effectively improves symptoms, hemodynamics and probably prognosis. Long-term results are well known, but patients' preference and the number of experienced surgical centers are fading. Randomized studies are missing. 2. TASH induces quite similar improvements in symptoms and hemodynamics. It is remarkably evaluated for a postprocedural follow-up of up to 10 years, and it is the preferred mode of treatment in patients. However, information on long-term prognosis, rhythmogenic effects and randomized studies are missing. For the prevention of sudden death, TASH has to be combined with an ICD. 3. Dual-chamber pacing was evaluated in randomized crossover studies, but symptomatic and hemodynamic improvements and patients' preference are substantially lower than for TASH. 4. The ICD has the potential to alter prognosis in secondary (class I indication) and primary prevention. HCM patients should undergo a risk stratification assessment. Prophylactic implants base on a clinical profile with two or more risk markers (sometimes one risk marker). 5. Ablation of atrial fibrillation or the AV node is indicated to improve symptoms in patients with fast ventricular rates despite medical treatment. For the prevention of sudden death, it has to be combined with an ICD.

[Multi-slice CT of aortocoronary venous bypasses and mammary artery bypasses: evaluation of bypasses and their anastomoses]. / Mehrzeilen-Spiral-CT von aortokoronaren Venenbypässen und Mammaria-interna-Bypässen: Beurteilung der Bypässe und ihrer Anastomosen.

OBJECTIVE: To assess aortocoronary grafts and internal mammary artery bypasses by means of EKG-triggered contrast-enhanced multi-slice spiral CT, and to evaluate the diagnostic accuracy of this new imaging modality. MATERIAL AND METHODS: 59 patients with up to 5 aortocoronary grafts and/or internal mammary artery bypasses per patient were examined with regard to bypass morphology, the free passage, and the proximal as well as the distal anastomoses using multislice computed tomography. Axial source images were calculated by means of retrospective triggering at different diastolic delay times, and were postprocessed in several planes with the multiplanar volume reconstruction (MPVR) software. RESULTS: On the pre-condition that data sets were acquired at sinus rhythm and at a heart rate lower than 65/min, aortocoronary grafts and internal mammary artery bypasses could be depicted in adequate diagnostic quality in about 80% of all cases with contrast-enhanced multi-slice spiral CT. Both, the free passage of the bypasses as well as the morphology of the proximal anastomoses were sufficiently assessed with multiplanar volume reconstruction (MPVR), whereas the distal anastomoses couldn't be depicted sufficiently in 20% of all cases. CONCLUSION: As a non-invasive method, contrast-enhanced and ECG-triggered multi-slice spiral computed tomography has gained diagnostic potential for the accurate visualization of aortocoronary grafts and the internal mammary artery bypasses.