Current alternatives to traditional radial approach for coronary interventions: A randomized prospective study of the ulnar and distal radial approaches.

BACKGROUND: The radial artery is the standard access for coronary intervention; however, it is essential to have alternative accesses as it may be used as a conduit during coronary artery bypass grafting or for dialysis fistula. Ulnar and distal radial artery accesses have emerged as alternative accesses for traditional radial artery. AIM: To compare distal radial artery access and ulnar artery access as alternatives to traditional radial artery access regarding safety, efficacy, and success rate. METHODS: Two-hundred patients were included (100 traditional radial [TRA], 50 distal radial [DRA] and 50 ulnar). Access artery follow up ultrasound was performed up to 28 days. RESULTS: Procedural success rate was 97%, 74%, and 92% in the TRA, DRA and ulnar groups, respectively (p < 0.001). Crossover occurred in 3 patients (3%) in TRA, 13 patients (26%) in DRA and 4 cases (8%) in ulnar group (p < 0.001). The most common cause of crossover was failure of artery cannulation. Regarding cannulation time, the mean access time in seconds was 80.19 ± 25.98, 148.4 ± 29.60, 90.5 ± 21.84 in TRA, DRA and ulnar groups, respectively (p < 0.001). CONCLUSIONS: Our study concluded that these new approaches proved to be potential alternatives to traditional radial approach; however, ulnar artery access proved to be superior to distal radial artery access as regards success rate and cannulation time.

Coronary calcifications, the Achilles heel in coronary interventions.

Percutaneous coronary intervention in severely calcified coronaries has been associated with higher rates of procedural complications, including myocardial infarction and death in addition to increased frequency of coronary revascularization on an intermediate and long-term basis. The SYNTAX score, which is designed to assess the complexity of coronary artery disease and aids in choosing a revascularization method, allocates two points per lesion when there is heavy calcification present on fluoroscopy. With the advent of novel multimodality imaging technologies, the detection and evaluation of coronary calcifications improved significantly over the last decade. Several tools are now available for modifying calcified lesions including different types of dedicated balloons and atherectomy devices, which may create some degree of confusion regarding the suitable application of each instrument. The aim of this review is to cover this vital topic from different aspects. First, we tried to provide an overview on the pathophysiology and types of coronary calcification and its risk factors. Then, we outlined the available imaging modalities for the evaluation of calcified coronary lesions, highlighting the points of strength and weakness of each of them. A comprehensive discussion of calcium-modifying techniques was elaborated, summarizing their mechanism of action, pros and cons, and possible complications. Finally, an integrated algorithm was proposed for the best management of calcified coronary lesions.

The utility and effectiveness of the newer generation high-resolution coronary computed tomography angiography in the evaluation of coronary in-stent restenosis.

BACKGROUND: The importance of coronary computerized tomography angiography (CCTA) in detecting native coronary artery stenosis has been established. However, very few studies investigated the efficacy of CCTA in the assessment of in-stent restenosis (ISR) in symptomatic patients after percutaneous coronary intervention (PCI). AIM OF THE STUDY: To evaluate the value of CCTA in diagnosing ISR. METHODS: We included 102 symptomatic patients with stable angina, presented one to five years after PCI. All patients were subjected to CCTA, and the patients with significant coronary artery disease were directed for invasive coronary angiography (ICA). CCTA results were compared to ICA as the gold standard tool for detecting ISR. RESULTS: In 88 (86.3 %) patients, CCTA could successfully exclude ISR together with the ICA (true negative), but in two cases, ICA detected an ISR which was not detected by CCTA (false negative). In eight patients, CCTA detected ISR. These were confirmed by ICA (true positive) and revascularized. In four patients (3.9 %), ISR was suspected by CCTA but excluded by ICA (false positive). In our study, according to the agreement of CCTA in detection or exclusion of ISR, sensitivity, specificity, PPV, NPV and accuracy were 80.0 %, 96.65 %, 66.67 %, 97.78 %, 94.12 %, respectively. These results were statistically significant (P < 0.001). CONCLUSIONS: In up to 86 % of symptomatic patients with previous PCI, ISR was accurately excluded by CCTA. CCTA was demonstrated by this study as a high yielding tool for ruling out ISR, abolishing the need for more invasive and expensive diagnostic procedures.

Right Ventricular Response to Cardiac Resynchronization Therapy: A Three-Dimensional and Speckle Tracking Echocardiographic Study.

Cardiac resynchronization therapy (CRT) induces left ventricle reverse remodeling; however, its effects on right ventricular (RV) volumes and function were not well described. This study aimed to assess the effects of CRT on RV. Of 112 patients, 63 enrolled with a mean age of 62.77 ± 7.23 years, including 40 males (63.5%). All patients met criteria for CRT implantation and were followed at 3-month and 6-month intervals. Standard 2-dimensional/3-dimensional (3D) echocardiography and speckle-tracking analyses were conducted for assessment of LV and left atrium (LA). RV maximum diameters, tricuspid lateral annular systolic velocity, tricuspid annular plane systolic excursion, fractional area change, RV global (RV 4-chamber strain (RV4CSL), and RV free wall strain (RVFWSL), in addition to 3D echocardiographic assessment of RV, were done before CRT implantation and at follow-up visits. Mean follow-up period was 6.76 ± 1.25 months. A total of 48 patients (76.2%) were LV responders (LVR) whereas the rest were nonresponders (LVNR). Both groups had similar baseline characteristics, risk factors, device implantation, and programming values. Only LVR had significant reduction in RV basal diameter, together with significant improvement of RV systolic performance: systolic velocity, fractional area change, RV4CSL, RVFWSL, and 3D-derived RV volumes and ejection fraction, compared with baseline values. In addition, pulmonary arterial systolic pressure decreased in LVR with reduction of tricuspid regurgitation severity. LV response, percentage change of RV4CSL, LA end-systolic volume index, and LA emptying fraction at 3-month follow-up were the most independent predictors of RV response by multivariate analysis. Reduced left ventricular end-systolic volume >13.5% had 92.3% sensitivity and 81.8% specificity. In conclusion, CRT-induced RV reverse remodeling and improved RV-arterial coupling. These effects were associated with left side response to CRT.

Effects of cardiac pacemakers on left ventricular volumes and function assessed by 3D echocardiography, Doppler method, and global longitudinal strain.

BACKGROUND: Many previous studies reported the negative effects of right ventricular (RV) pacing on the left ventricular (LV) structure and ejection fraction. Studying pacing hemodynamics is essential to understand these detrimental effects. In this study, we tried to understand RV pacing effects on LV volumes and function using advanced tools like 3D echo and global longitudinal strain (GLS). This was a prospective study of 175 consecutive patients (LVEF>50%) presented permanent pacing. Of 175 patients, only 50 patients met study criteria, divided into two groups (single or dual pacing). LV volumes and function were assessed by full-volume 3D echocardiography and GLS before pacing, at 1-week and 6-month post-pacing. Cardiac output (COP) was calculated by pulsed wave Doppler method and 3D echo. RESULTS: Doppler method results were similar to 3D echo in calculating SV and COP. At 1-week post pacing, both groups showed a significant decrease in SV due to a drop in EDV while ESV did not change significantly. Despite the drop in SV, there was a significant increase in cardiac output (COP) due to achieving higher heart rates post-pacing. There was a significant drop in EF and GLS in both groups. At 6 months, SV continued to decrease with a corresponding decrease in COP and LVEF. This drop in SV was due to a significant increase in ESV while EDV did not show a significant change at a 6-month follow-up. Also, the drop EF and GLS became more significant. There were no significant differences between both groups regarding the changes in LV volumes (EDV, ESV, SV), LVEF or GLS throughout the study (pre-pacing, at 1-week and 6-months post pacing). However, dual-chamber pacing group provided higher heart rates and as a result higher COP than the single-chamber group. CONCLUSIONS: RV pacing led to a significant drop in LV COP, ejection fraction (EF), and GLS over short- and long-term duration. Dual chamber pacing provided higher COP than a single chamber pacing. This was due to tracking the S. A node with pacing at higher heart rates not due to an increase in SV and preserving atrioventricular synchrony. Both Doppler method and 3D echo can be used to calculate SV and COP.

Predictors of pacing induced left ventricular dysfunction and cardiomyopathy assessed by three-dimensional echocardiography and speckle tracking strain.

BACKGROUND: Long-term RV pacing leads to ventricular dyssynchrony, in the form of LBBB-like morphology, with subsequent detrimental effects on LV structure and function. Three-dimensional echocardiography allowed early detection of volumetric changes associated with PICMP and provided more accurate assessment of mechanical dyssynchrony. Speckle tracking strain is able to identify LV dysfunction even before any reduction in LVEF. Our aim was to study pacing effects on LV function and hemodynamics using 3D echo and speckle tracking strain. RESULTS: This was a prospective study of 175 consecutive patients without structural heart disease (LVEF > 50%) presented for permanent pacing. Full-volume 3D echocardiography done before implantation, 1 week, and 6 months together with GLS. Patients were followed for 6 months to detect incidence of PIVD (defined as reduction in LVEF > 10% but still above 50%) and PICMP (defined as decrease in LVEF by 10% from baseline in absence of other known causes of cardiomyopathy resulting in EF< 50%). PIVD and PICMP predictors and risk factors were analyzed. Only 50 patients met study criteria. Twenty-five (50%) patients developed LV systolic dysfunction; of these, 19 (38%) developed PIVD and 6 (12%) developed PICMP. Pre-implantation GLS was significantly lower in the 6 patients who subsequently developed PICMP, compared to those who developed PIVD and the preserved EF group (mean GLS - 15.50 vs. - 21.0, - 20.0 respectively; p = 0.005, 0.033, respectively). At 1 week, GLS was significantly lower in the 25 patients who subsequently developed PIVD, compared to those who did not (GLS - 13.0 vs. - 18.0, respectively; p = 0.002). A reduction of baseline GLS by 15% or more at 1 week was associated with the development of PIVD and PICMP (p = < 0.001). A wider native QRS complex was associated with PIVD and PICMP (p = 0.008, 0.018, respectively). The other predictors were found non-significant. CONCLUSION: PICMP may be more common than previously reported and it may occur shortly after implantation. Pre-implantation GLS is a sensitive parameter for PICMP. One-week GLS, pre-implantation QRS complex width are early predictors for PICMP and PIVD before any reduction in EF.