Mitochondrial Dysfunction and Heart Diseases
Shamim I. Ahmad in Handbook of Mitochondrial Dysfunction, 2019
Heart diseases are among the leading causes of death worldwide. Hypertension and ageing are not only the most common causes of left ventricular hypertrophy and diastolic dysfunction, but also impose significant risks of coronary heart disease, congestive heart failure, stroke and sudden death (arrhythmia). Understanding the role of mitochondrial dysfunction and signaling in aging and hypertensive cardiomyopathy, pressure-overload induced heart failure and arrhythmia will assist the development of strategies to prevent or ameliorate cardiac hypertrophy and failure, or even to delay cardiac aging changes. Since mitochondrial dysfunction is one major mechanism leading to heart diseases, the small molecule drugs that can protect mitochondria may become attractive potential novel therapeutics for patients with heart diseases. Several drugs have been developed, including mitochondrial targeted antioxidants, such as triphenylalkylphosphonium (TPP+) conjugated coenzyme Q (MitoQ) and plastoquinone (SkQ1)147,148 and Elamipretide (SS31) that targeted to mitochondrial inner membranes enriched with cardiolipin. These small molecules have shown promising results in various pre-clinical models of heart diseases. Several phase II and phase III clinical trials are being performed to study the effect of Elamipretide in heart failure and mitochondrial myopathies.149,150. The roles of these mitochondrial protective interventions in cardiac aging and arrhythmia also warrant further clinical investigations.
Testing the master athlete
R. C. Richard Davison, Paul M. Smith, James Hopker, Michael J. Price, Florentina Hettinga, Garry Tew, Lindsay Bottoms in Sport and Exercise Physiology Testing Guidelines: Volume I – Sport Testing, 2022
Data from the UK suggest that myocardial disease typically accounts for 40% of SCD in all athletes, being more prevalent in older athletes. The predominant causes were idiopathic left ventricular hypertrophy (LVH) and/or fibrosis and arrhythmogenic right ventricular cardiomyopathy (ARVC) (Finocchiaro et al., 2016). The majority of athletes died during exertion (61%), and only a minority of subjects (8%) had a family history of sudden death. Unfortunately, we do not know the relationship between age and circumstances of death, but many of the fatalities at rest are related to sudden arrhythmic death syndrome (SADS), which is more common in the younger athlete. The older athlete is more likely to die during exercise with coronary artery disease (CAD) as the predominant cause of SCD (Chugh and Weiss, 2015; Finocchiaro et al., 2016). The significantly lower prevalence of arrhythmias in the older population suggests that pre-participation electrocardiogram (ECG) screening may be of limited use although data from Jensen-Urstad et al. (1998) suggest that abnormal arrhythmias are highly prevalent in elderly (>70 yr of age) lifelong strenuous exercisers. Indeed, the European Society of Cardiology updated their ECG screening criteria in 2010 to distinguish training-related and training-unrelated changes (Corrado et al., 2010). Morrison et al. (2016) suggested that while cardiac screening protocols do exist around the world, researchers have not yet systematically and extensively evaluated them, particularly for their suitability for master athletes.
Valve Disease
Mary N. Sheppard in Practical Cardiovascular Pathology, 2022
Supravalvar aortic stenosis is the least common type of left ventricular outflow obstruction (seeFig. 3.29a) and most patients with this condition have Williams syndrome. Williams syndrome is also known as idiopathic infantile hypercalcaemia and patients go on to develop renal calcification. It is a rare multi-system genomic disorder, caused by 7q11.23 microdeletion with a prevalence of 1/7500–1/20 000 live births. Virtually all cases have mental retardation, with characteristic elfin-type faces. There is disordered mosaic architecture in the elastic tissue of the aortic media giving rise to a hypoplastic thickened aorta with congenital supravalvar aortic stenosis. The lesion may be present as a discrete shelf, as a so-called hour-glass deformity or as a tubular variety in which most of the aortic arch and its branches are thickened, which is the rarest. The coronary arteries arise from the segment under high pressure and this causes them to become dilated and tortuous with early onset of atherosclerosis. This, in combination with left ventricular hypertrophy is responsible for sudden deaths in this condition. Mortality is highest in patients with multilevel obstruction.
Impact of iron deficiency on exercise capacity and outcome in heart failure with reduced, mid-range and preserved ejection fraction
Published in Acta Cardiologica, 2018
Pieter Martens, Petra Nijst, Frederik H. Verbrugge, Kevin Smeets, Matthias Dupont, Wilfried Mullens
All patients were recruited in a single tertiary care centre (Ziekenhuis Oost-Limburg, ZOL Genk, Belgium) between August 2008 and January 2016. The current study cohort is the result of a pooled analysis of five different investigator-initiated prospective studies all preformed at ZOL Genk with overlapping design in terms of collection of baseline and clinical outcome data. Overlapping entry-criteria included a previous heart failure hospitalisation and heart failure with reduced ejection fraction (defined as an LVEF <45%) or preserved ejection fraction [LVEF >45%, with one additional echocardiographic alteration: (i) left ventricular hypertrophy, (ii) left atrial dilatation, (iii) diastolic dysfunction]. However, for the current analysis (in effort to adhere to current European Heart Failure Guidelines), patients were categorised into three groups based on ejection fraction: (1) HFrEF = LVEF <40%, (2) HFmrEF = LVEF 40–50% and (3) HFpEF = LVEF >50%. Precise inclusion and exclusion criteria per cohort are available in Supplementary Table 1. All study protocols were approved by the institutional review board and all patients provided written informed consent. This study complies with the declaration of Helsinki. The manuscript was drafted according to the STROBE-statement for observational studies [6].
Usefulness of non-gated chest computed tomography scans in the diagnosis of acute myocardial infarction
Published in Baylor University Medical Center Proceedings, 2022
Ahmad Jabri, Laith Alhuneafat, Anas Alameh, Ahmad Al-abdouh, Mohammed Mhanna, Hani Hamade, Farhan Nasser, Adnan Yousaf, Ashish Aneja
A 64-year-old woman with hypertension, hyperlipidemia, and diabetes mellitus type 2 presented to the ED complaining of sudden back pain radiating to her anterior chest for 1 day. Her pain was associated with shortness of breath, nausea, and emesis. The initial electrocardiogram showed ST elevation in precordial lead V1 and a troponin T level of 0.746 µg/mL (normal < 0.10). The patient was given aspirin and nitroglycerin. Chest CT with an aortic dissection protocol was negative for aortic dissection but showed three-vessel CAD with decreased enhancement of the septum/apex (Figure 1a). An echocardiogram showed a left ventricular ejection fraction of 55% with severe hypokinesis of the mid anteroseptal, mid anterior free wall, mid inferior wall, and entire apex. Concentric left ventricular hypertrophy was also present. Right ventricular systolic function was normal. Cardiac catheterization revealed a complete proximal left anterior descending (LAD) artery, which was stented with a drug-eluting stent (Figure 1b).
Relation between fragmented QRS complex and cardio-ankle vascular index in asymptomatic subjects
Published in Clinical and Experimental Hypertension, 2021
Ali Rıza Akyüz, Sinan Şahin, Ömer Faruk Çırakoğlu, Selim Kul, Turhan Turan, Hakan Erkan
The major limitation of our study was limited sample size. As our study had a cross-sectional one, causal associations were not certain. Moreover, we did not thoroughly investigate our patients for the presence of left ventricular hypertrophy, i.e. increased LV mass, using echocardiography. According to our opinion, such limitations may have effects on our arterial stiffness measurements. However, we solely intended to investigate the relationship between fQRS and arterial stiffness. Investigation of other confounding factors was not the primary aim of the present study. ECG is a widely and readily available, inexpensive, reproducible technique that can be examined by almost every physician. Our study pioneers in establishing a link between a cheap and simple diagnostic technique and a clinically meaningful outcome.
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