The effect of age on mechanisms of exercise tolerance: Reduced arteriovenous oxygen difference causes lower oxygen consumption in older people.

OBJECTIVE: To assess the effect of age on mechanisms of exercise tolerance. METHODS: Prospective observational study recruited 71 healthy individuals divided into two groups according to their age i.e. younger (≤40 years of age, N = 43); and older (≥55 years of age, N = 28). All participants underwent maximal graded cardiopulmonary exercise stress testing using cycle ergometer with simultaneous non-invasive gas-exchange and central haemodynamic measurements. Using the Fick equation, arteriovenous O2 difference was calculated as the ratio between measured O2 consumption and cardiac output. RESULTS: The mean age of younger and older participants was 26.0 ± 5.7 years, and 65.1 ± 6.6 years respectively. Peak O2 consumption was significantly lower in older compared to the younger age group (18.8 ± 5.2 vs 34.4 ± 9.8 mL/kg/min, p < 0.01). Peak exercise cardiac output and cardiac index were not significantly different between the younger and older age groups (22.7 ± 5.0 vs 22.1 ± 3.9 L/min, p = 0.59; and 12.4 ± 2.9 vs 11.8 ± 1.9 L/min/m2, p = 0.29). Despite demonstrating significantly lower peak heart rate by 33 beats/min (129 ± 18.3 vs 162 ± 19.9, p < 0.01), older participants demonstrated significantly higher stroke volume and stroke volume index compared to the younger age group (173 ± 41.5 vs 142 ± 34.9 mL/min, p < 0.01; and 92.1 ± 18.1 vs 78.3 ± 19.5 mL/m2, p < 0.01). Arteriovenous O2 difference was significantly lower in older compared to younger age group participants (9.01 ± 3.0 vs 15.8 ± 4.3 mlO2/100 mL blood, p < 0.01). CONCLUSION: Ability of skeletal muscles to extract delivered oxygen represented by reduced arteriovenous O2 difference at peak exercise appears to be the key determinant of exercise tolerance in healthy older individuals.

Transcatheter aortic valve implantation in an orthotopic heart transplant recipient with bicuspid aortic valve.

Increasing longevity of heart transplantation recipients and aging donor population accompanied by the older age at transplantation led to an increase in the prevalence of degenerative valvular disease in particular aortic stenosis. TAVI is considered a safe and feasible alternative compared to conventional SAVR in this high-risk population.

Age is not a bar to PCI: Insights from the long-term outcomes from off-site PCI in a real-world setting.

OBJECTIVES: We sought to analyze the percutaneous coronary intervention (PCI) outcomes of very elderly patients (V. Eld. group, age >80 years) and compare their outcomes to a less elderly cohort (Eld. group, age 75-80 years) traditionally reported in the literature. BACKGROUND: Limited data exist on peri-procedural and long-term outcomes following PCI in the V. Eld. (age >80 years), with under-representation of this cohort in randomized controlled trials. These patients present with advanced complex coronary disease and multiple comorbidities. METHODS: All 580 consecutive patients aged ≥75 years (age 80 ± 4.9 years, 57.4% males) undergoing PCI between April 2006 and November 2011 were included. A total of 624 consecutive lesions were identified and analyzed. All V. Eld. patients (n = 253) were subsequently selected, and their outcomes compared to Eld. patients (n = 327). Mean follow-up was 30.8 ± 2.7 months with 98% clinical follow-up achieved. RESULTS: All comparative data are expressed as (V. Eld. vs Eld.) unless otherwise specified. All-cause mortality was significantly higher in the V. Eld. group (11.9% vs 6.1%), although this did not translate into a significant difference in cardiac mortality (6.3% vs 3.7%) or major adverse cardiac and cerebrovascular events (16.2% vs 12.5%). The composite incidence of myocardial infarction (MI), stroke, definite/probable stent thrombosis, and TIMI major bleed was 4.7%, 1.4% 1.9%, and 6.4%, respectively with no significant difference between both cohorts. CONCLUSIONS: This study demonstrates an acceptable occurrence of MI, death, repeat intervention, and stent thrombosis in a high-risk group of V. Eld. patients with de novo lesions. Age alone in the absence of other non-cardiac factors should not prohibit a patient from access to PCI.

Direct transfemoral transcatheter aortic valve implantation without balloon pre-dilatation using the Edwards Sapien XT valve.

OBJECTIVES: To evaluate the feasibility and safety of direct transcatheter aortic valve implantation (TAVI) by the transfemoral approach without balloon pre-dilatation using the Edwards SapienXT valve. BACKGROUND: TAVI is established in selected high-risk patients with severe aortic stenosis. Balloon aortic valvuloplasty (BAV) is recommended prior to valve implantation, but may contribute to procedural risk. It is unknown whether this is necessary for successful passage and deployment of the device. METHODS: 81 patients (mean age 84 [95%CI:82-85.8], 62% male, median EuroScore 22.8% [95%CI:20.5-27]) undergoing transfemoral TAVI (35 by direct implantation [direct group]; 46 with balloon pre-dilatation [balloon group]) between 2010 and 2013 were analyzed for efficacy and safety endpoints. RESULTS: Procedural success was 100%. Pre and post-procedural peak gradients in the direct group were 66mmHg (95%CI:59-72.8) and 14mmHg (95%CI:12-17.8)(P < 0.0001) compared to 76.5mmHg (95%CI:73.7-94.0) and 17mmHg (95%CI:16-19)(P < 0.0001) in the balloon group. Post-dilatation was performed in 4/35(11.4%) of the direct group and 3/46(6.5%) of the balloon group (P = 0.83). Post procedure moderate AR was present in 1/35(2.9%) in the direct group and none in the balloon group. In-hospital mortality (2.9% direct vs. 0% balloon group), stroke (2.9% vs. 4.4%), tamponade (2.9% vs. 2.2%), major vascular complications (2.9% vs. 8.7%) and new permanent pacing (2.2% vs. 0) were similar. Pacing time, inflations, radiation dose and contrast use were all significantly lower in the direct group. CONCLUSIONS: Direct implantation of the Edwards SapienXT valve during TAVI by the transfemoral route appears safe, efficacious and feasible in those without extreme calcification. © 2016 Wiley Periodicals, Inc.

Neurocardiogenic syncope: a rare presentation of pharyngeal lymphoma.

Syncope is a common symptom of patients attending emergency departments, yet presents significant diagnostic and therapeutic challenges. We present a rare cause of recurrent vasovagal syncope with predominant cardioinhibitory response due to lymphoma surrounding and compressing the carotid artery treated successfully with radiotherapy.