New echocardiographic screening tool for left ventricular tract obstruction risk assessment in TMVR.

BACKGROUND: Transcatheter mitral valve replacement (TMVR) is an alternative to conventional surgery to treat severe mitral disease but its use is limited by the risk of left ventricular outflow tract obstruction (LVOTO). Screening depends on ECG-gated computed tomography (CT) that is not widely available and requires contrast. We developed and validated a transthoracic echocardiographic (TTE) method to assess the risk of LVOTO after TMVR with the Tendyne System. METHODS: We measured the LVOT longitudinal area on preoperative TTE dataset of patients screened for TMVR. The LVOT was measured as the box-area included by the aortic valve annulus, the anterior mitral leaflet (AML), the c-septum distance line, and the respective length of the AML on the interventricular septum. We analyzed the correlation between the TTE LVOT-box and the CT-measured neoLVOT area. Prediction performance for eligible patients was tested with ROC curves. RESULTS: Thirty-nine patients were screened, out of 14 patients (36%) not eligible for TMVR, 8 had risk of LVOTO. We found a linear correlation between the TTE LVOT-box and the CT-measured Neo-LVOT (r = 0.6, p = 0.002). ROC curve showed that the method is specific and sensitive and the cut-off value of the measure LVOT-box is 350 mm2. CONCLUSIONS: The proposed method is reliable to evaluate the risk of LVOTO after TMR with the Tendyne System. It is quick and easy and can be used as a first-line assessment in the outpatient clinic. Patients with LVOT-box <350 mm2 should not be further screened with ECG-gated cardiac CT.

Use of Cardiac Contractility Modulation in an Older Patient with Non-Ischemic Dilated Cardiomyopathy: A Case Report.

Cardiac contractility modulation (CCM) is a novel device-based therapy used in patients with HFrEF. CCM therapy is associated with an improvement in exercise tolerance, increased quality of life, reduced HF hospitalizations, and reverse remodelling of the left ventricle in patients with HFrEF. In this case, we report the clinical benefit of CCM in an older patient with advanced HFrEF due to ischemic dilated cardiomyopathy with frequent heart failure-related hospitalizations and poor quality of life despite optimal medical therapy.

Ultrasound-guided venipuncture for implantation of cardiac implantable electronic devices: A single-center, retrospective study.

BACKGROUND: The venous access for the insertion of permanent leads of cardiac implantable electronic devices is often achieved by venous cutdown of the cephalic vein, or by "blind" puncture of the subclavian vein using anatomical landmarks, or by fluoroscopy-assisted methods. METHODS: We have retrospectively analyzed our clinical experience to verify the feasibility, the safety, and efficacy of the adoption of ultrasound-guided puncture/cannulation of the axillary vein for this purpose. RESULTS: Nine hundred eighty-seven leads were placed during 548 consecutive procedures, accessing the axillary vein in the infraclavicular area using real-time ultrasound guidance. Venipuncture was successful in 99.8% of cases. The access time was 11 seconds (range 4-580). We recorded three cases of pneumothorax (0.5%), but no hemothorax and no hemo-mediastinum. The incidence of local hematoma was 2.1% (12 cases). No injury to the brachial plexus or to the phrenic nerve was recorded. In a follow-up of 33 months (range 16-39), we observed no cases of "subclavian crush syndrome" (damage of the leads at the level of the thoracic inlet), and the rate of pocket infection/infective endocarditis was 0.7%. CONCLUSION: In our experience, ultrasound-guided puncture/cannulation of the axillary vein for implantation of permanent leads is feasible, effective, and safe. It might be considered as a first option for this procedure.

Are implantable cardiac monitors reliable tools for cardiac arrhythmias detection? An intra-patient comparison with permanent pacemakers.

INTRODUCTION: Implantable cardiac monitor (ICM) is an established tool for the management of unexplained syncope and atrial fibrillation (AF) even if its accuracy of arrhythmia detection may be suboptimal. The aim of this study was to perform an intra-patient comparison of the diagnostic capability of ICM with a dual-chamber PM as a gold standard. METHODS: We included 19 patients with a previously implanted ICM (BioMonitor 2 Biotronik, Berlin, Germany), who received a dual-chamber PM for standard indications. ICM-detected arrhythmic events in a 6-month follow-up were compared with those detected by the PM and classified by visual inspection of intracardiac electrograms. RESULTS: During follow up, ICMs generated 15 false asystole and 39 false bradycardia detections in 5 patients (26.3%) due to recurrent premature ventricular contractions. A total of 34 true high ventricular rate (HVR) episodes were detected by the PM. Of them, 30 (88%) events were also recorded by the ICM, which further detected 14 false HVR snapshots, leading to a sensitivity and positive predictive value of 88% and 68%, respectively. In addition, PM identified 234 true AF episodes. Of them, 225 (96%) events were also detected by the ICM, while 8 (42%) ICMs stored 50 AF episodes classified as false positives. The ICM sensitivity for AF was 96% with a positive predictive value of 82%. CONCLUSION: Our intra-patient comparison with permanent PM confirmed that ICM is an effective tool for cardiac arrhythmias detection. ICM algorithms for AF and HVR detection were highly sensitive with an acceptable rate of false positive episodes.

Pacemaker pocket infection: Innovative conservative treatment in elderly patients with no signs of systemic infection.

BACKGROUND: The gold standard to treat cardiovascular implantable electronic devices (CIEDs) infections is the complete system removal. The aim of this retrospective analysis is to assess the feasibility and safety of an alternative conservative surgical system revision approach, to be applied in elderly patients who refused the extraction procedure, in case of no signs of systemic infection. METHODS: Between May 2009 and January 2019, we performed system revision of 25 patients (15 men and 10 women, median age 81 [IQ: 75-85] years) with negative blood culture, no signs of vegetation, who experienced CIED infections. RESULTS: In all patients the following surgical procedure was applied: the pocket was opened, the wound's necrotic tissue was dissected en bloc; fibrotic tissue was excised. The pocket was washed with hydrogen peroxide and saline solution. The pocket was then closed without implanting the device and left with a continuous infusion of antibiotics and normal saline for 4 days. Subsequently the new generator was implanted, possibly in a different pocket than the previous one. All patients underwent a median follow up of 24 [IQ: 14-34] months. In 24 patients out of the 25 observed the procedure was safe and effective, except for one patient who needed the extraction. CONCLUSIONS: The two-stage surgical revision technique is feasible and safe. It may be considered for elderly patients who refused extraction and presented no signs of systemic infection or in some categories of patients. In case of failure of the procedure, subsequent treatment with complete extraction of the system would not be precluded.

Implantable loop recorder in clinical practice.

The implantable loop recorder (ILR), also known as insertable cardiac monitor (ICM) is a subcutaneous device used for diagnosing heart rhythm disorders. These devices have been strongly improved and miniaturized during the last years showing several reliable features along with the availability of remote monitoring which improves the diagnostic timing and the follow-up strategy with a potential reduction of costs for health care. The recent advent of injectable ILRs makes the procedure even easier and more tolerated by patients. ILR allows the investigation of unexplained recurrent syncope with uncertain diagnosis, revealing a possible relationship with cardiac arrhythmias. In addition, it has recently been equipped with sophisticated algorithms able to detect atrial fibrillation episodes. This new opportunity may provide to the physicians systematic heart rhythm screening with possible effects on patient antiarrhythmic and anticoagulant therapy management. The use of such devices will surely increase, since they may be helpful to diagnose a wide range of disorders and pathologies. Indeed, further studies should be performed in order to identify all the potentialities of these tools.

Increased tissue oxygenation explains the attenuation of hyperemia upon repetitive pneumatic compression of the lower leg.

The rapid hyperemia evoked by muscle compression is short lived and was recently shown to undergo a rapid decrease even in spite of continuing mechanical stimulation. The present study aims at investigating the mechanisms underlying this attenuation, which include local metabolic mechanisms, desensitization of mechanosensitive pathways, and reduced efficacy of the muscle pump. In 10 healthy subjects, short sequences of mechanical compressions (n = 3-6; 150 mmHg) of the lower leg were delivered at different interstimulus intervals (ranging from 20 to 160 s) through a customized pneumatic device. Hemodynamic monitoring included near-infrared spectroscopy, detecting tissue oxygenation and blood volume in calf muscles, and simultaneous echo-Doppler measurement of arterial (superficial femoral artery) and venous (femoral vein) blood flow. The results indicate that 1) a long-lasting (>100 s) increase in local tissue oxygenation follows compression-induced hyperemia, 2) compression-induced hyperemia exhibits different patterns of attenuation depending on the interstimulus interval, 3) the amplitude of the hyperemia is not correlated with the amount of blood volume displaced by the compression, and 4) the extent of attenuation negatively correlates with tissue oxygenation (r = -0,78, P < 0.05). Increased tissue oxygenation appears to be the key factor for the attenuation of hyperemia upon repetitive compressive stimulation. Tissue oxygenation monitoring is suggested as a useful integration in medical treatments aimed at improving local circulation by repetitive tissue compression.NEW & NOTEWORTHY This study shows that 1) the hyperemia induced by muscle compression produces a long-lasting increase in tissue oxygenation, 2) the hyperemia produced by subsequent muscle compressions exhibits different patterns of attenuation at different interstimulus intervals, and 3) the extent of attenuation of the compression-induced hyperemia is proportional to the level of oxygenation achieved in the tissue. The results support the concept that tissue oxygenation is a key variable in blood flow regulation.