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Fulltext Intramyocardial dissecting haematoma mimicking left ventricular clot, a rare complication of myocardial infarction: a case report

Lee TJ, Roslan A, Teh KC, Ghazi A

Eur Heart J Case Rep, 2019 Jun 01;3(2).
PMID: 31449618 DOI: 10.1093/ehjcr/ytz056

BACKGROUND: Intramyocardial dissecting haematoma is a rare complication of myocardial infarction (MI) associated with high mortality rates. Studies and research of this occurrence are limited largely to isolated case reports or case series.
CASE SUMMARY: We report a case of late presenting MI, where on initial echocardiogram had what was thought to be an intraventricular clot. However, upon further evaluation, the patient actually had an intramyocardial haematoma, with the supporting echocardiographic features to distinguish it from typical left ventricular (LV) clot. While this prevented the patient from receiving otherwise unnecessary anticoagulation, this diagnosis also put him at a much higher risk of mortality. Despite exhaustive medical and supportive management, death as consequence of pump failure occurred after 2 weeks.
DISCUSSION: This report highlights the features seen on echocardiography which support the diagnosis of an intramyocardial haematoma rather than an LV clot, notably the various acoustic densities, a well visualized myocardial dissecting tear leading into a neocavity filled with blood, and an independent endocardial layer seen above the haematoma. Based on this report, we wish to highlight the importance of differentiating intramyocardial haematomas from intraventricular clots in patients with recent MI.
Fulltext An Asian regional analysis of cost-effectiveness of early irbesartan treatment versus conventional antihypertensive, late amlodipine, and late irbesartan treatments in patients with type 2 diabetes, hypertension, and nephropathy

Annemans L, Demarteau N, Hu S, Lee TJ, Morad Z, Supaporn T, et al.

Value Health, 2008 May-Jun;11(3):354-64.
PMID: 17888064 DOI: 10.1111/j.1524-4733.2007.00250.x

OBJECTIVE: The prevalence of type 2 diabetes, often leading to diabetic nephropathy, has increased globally, especially in Asia. Irbesartan treatment delays the progression of kidney disease at the early (microalbuminuria) and late (proteinuria) stages of nephropathy in hypertensive type 2 diabetics. This treatment has proven to be cost-effective in Western countries. This study assessed the cost-effectiveness of early irbesartan treatment in Asian settings.
METHODS: An existing lifetime model was reprogrammed in Microsoft Excel to compare irbesartan started at an early stage to irbesartan or amlodipine started at a late stage, and standard treatments from a health-care perspective in China, Malaysia, Thailand, South Korea, and Taiwan. The main effectiveness parameters were incidences of end-stage renal disease, time in dialysis, and life expectancy. All costs were converted to 2004 US$ using official purchasing power parity. Local data were obtained for costs, transplantation,dialysis, and mortality rates. Probabilities regarding disease progression after treatment with the investigated drugs were extracted from two published clinical trials. A probabilistic sensitivity analysis was performed.
RESULTS: Early use of irbesartan yielded the largest clinical and economic benefits reducing need for dialysis by 61% to 63% versus the standard treatment, total costs by 9% (Thailand) to 42% (Taiwan), and increasing life expectancy by 0.31 to 0.48 years. Early irbesartan had a 66% (Thailand) to 95% (Taiwan) probability of being dominant over late irbesartan.
CONCLUSION: Although the absolute results varied in different settings, reflecting differences in epidemiology, management, and costs, early irbesartan treatment was a cost-effective alternative in the Asian settings.
Type E coronary artery dissection caused by intravascular lithotripsy balloon rupture; vessel anatomy and characteristics in a lithoplasty complication case as detailed by optical coherence tomography: a case report

Lee TJ, Wan Rahimi WFB, Low MY, Nurruddin AA

Eur Heart J Case Rep, 2021 Dec;5(12):ytab432.
PMID: 34993399 DOI: 10.1093/ehjcr/ytab432

Background: Intravascular lithotripsy is a new method used to treat calcified coronary lesions (CCLs). Percutaneous coronary intervention of CCLs has conventionally been classified as a complex procedure. In the majority of calcified cases, atherectomy is required for sufficient plaque modification prior to stent implantation. Intravascular lithotripsy has been shown to be safe and effective in clinical trials, but as worldwide usage increases, cases of complications are beginning to emerge.
Case summary: We describe a 71-year-old woman, who after an episode of non-ST-elevation acute coronary syndrome underwent coronary angiography. The culprit vessel was identified to be a severely stenosed left anterior descending artery which was also heavily calcified and tortuous. Intravascular lithotripsy (IVL) was employed for calcium modification prior to stent implantation, but the IVL balloon ruptured during shockwave lithotripsy, resulting in coronary artery dissection. Subsequent management steps and stent deployment resulted in favourable angiographic results. Our findings are further detailed on optical coherence tomography, demonstrating certain features which might predispose to IVL balloon rupture.
Discussion: We discuss the mechanism of action during intravascular lithotripsy, and how the shockwaves from the lithotripter modify calcified lesions, whilst keeping soft tissue unharmed. Results from clinical trials and multiple real-world studies have shown that complication rates are low. This case report aims to illustrate how the rupture of an intravascular lithotripsy balloon can result in coronary artery dissection. Optical coherence tomography can help in identifying potential anatomical features which may precede such complications.
Left ventricle geometry, atrial strain, ventricle strain, and hemodynamics across aortic valve before and after transcatheter aortic valve replacements

Roslan A, Tey YS, Ares F, Ashari A, Shaparudin A, Wan Rahimi WF, et al.

Med J Malaysia, 2022 Nov;77(6):736-743.
PMID: 36448393

INTRODUCTION: Transcatheter aortic valve replacements (TAVRs) has become widespread throughout the world. To date, there are no echocardiographic studies of TAVR patients from Southeast Asia (SEA). We sought to evaluate (1) changes in echocardiographic and strain values pre- and post-TAVR (2) relationship between aortic stenosis (AS) severity and strain values, (3) left ventricle geometry in severe AS, (4) relationship of flow rate to dimensionless index (DVI) and acceleration time (AT), and (5) effect of strains on the outcome.
MATERIALS AND METHODS: Retrospective study of 112 TAVR patients in our centre from 2009 to 2020. The echocardiographic and strain images pre (within 1 month), post (day after), and 6 months post-TAVR were analyzed by expert echocardiographer.
RESULTS: The ejection fraction (EF) increased at 6 months (53.02 ± 12.12% to 56.35 ± 9.00%) (p=0.044). Interventricular septal thickness in diastole (IVSd) decreased (1.27 ± 0.21 cm to 1.21 ± 0.23 cm) (p=0.038) and left ventricle internal dimension in diastole (LVIDd) decreased from 4.77 ± 0.64 cm to 4.49 ± 0.65 cm (p=0.001). No changes in stroke volume index (SVI pre vs 6 months p=0.187), but the flow rate increases (217.80 ± 57.61 mls/s to 251.94 ± 69.59 mls/s, p<0.001). Global longitudinal strain (GLS) improved from -11.44 ± 4.23% to -13.94 ± 3.72% (p<0.001), left atrial reservoir strain (Lar-S) increased from 17.44 ± 9.16% to 19.60 ± 8.77% (p=0.033). Eight patients (7.5%) had IVSd < 1.0 cm, and 4 patients (3.7%) had normal left ventricle (LV) geometry. There was linear relationship between IVSd and mean PG (r=0.208, p=0.031), between GLS to aortic valve area (AVA) and aortic valve area index (AVAi) (r = - 0.305, p=0.001 and r= - 0.316, p= 0.001). There was also relationship between AT (r=-0.20, p=0.04) and DVI (r=0.35, p<0.001) with flow rate. Patients who died late (after 6 months) had lower GLS at 6 months. (Alive; -13.94 ± 3.72% vs Died; -12.43 ± 4.19%, p=0.001).
CONCLUSION: At 6 months, TAVR cause reverse remodelling of the LV with the reduction in IVSd, LVIDd, and improvement in GLS and LAr-S. There is a linear relationship between GLS and AVA and between IVSd and AVA.
Catastrophic payments for health care in Asia

van Doorslaer E, O'Donnell O, Rannan-Eliya RP, Somanathan A, Adhikari SR, Garg CC, et al.

Health Econ, 2007 Nov;16(11):1159-84.
PMID: 17311356

Out-of-pocket (OOP) payments are the principal means of financing health care throughout much of Asia. We estimate the magnitude and distribution of OOP payments for health care in fourteen countries and territories accounting for 81% of the Asian population. We focus on payments that are catastrophic, in the sense of severely disrupting household living standards, and approximate such payments by those absorbing a large fraction of household resources. Bangladesh, China, India, Nepal and Vietnam rely most heavily on OOP financing and have the highest incidence of catastrophic payments. Sri Lanka, Thailand and Malaysia stand out as low to middle income countries that have constrained both the OOP share of health financing and the catastrophic impact of direct payments. In most low/middle-income countries, the better-off are more likely to spend a large fraction of total household resources on health care. This may reflect the inability of the poorest of the poor to divert resources from other basic needs and possibly the protection of the poor from user charges offered in some countries. But in China, Kyrgyz and Vietnam, where there are no exemptions of the poor from charges, they are as, or even more, likely to incur catastrophic payments.
Fulltext Disruptive environmental chemicals and cellular mechanisms that confer resistance to cell death

Narayanan KB, Ali M, Barclay BJ, Cheng QS, D'Abronzo L, Dornetshuber-Fleiss R, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S89-110.
PMID: 26106145 DOI: 10.1093/carcin/bgv032

Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically, the up-regulation of pro-survival factors, including oncogenic factors and antiapoptotic signaling pathways, and the down-regulation of pro-apoptotic factors, including tumor suppressive factors, confers resistance to cell death in tumor cells, which supports the emergence of a fully immortalized cellular phenotype. This review considers the potential relevance of ubiquitous environmental chemical exposures that have been shown to disrupt key pathways and mechanisms associated with this sort of dysfunction. Specifically, bisphenol A, chlorothalonil, dibutyl phthalate, dichlorvos, lindane, linuron, methoxychlor and oxyfluorfen are discussed as prototypical chemical disruptors; as their effects relate to resistance to cell death, as constituents within environmental mixtures and as potential contributors to environmental carcinogenesis.
Fulltext Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

Goodson WH, Lowe L, Carpenter DO, Gilbertson M, Manaf Ali A, Lopez de Cerain Salsamendi A, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S254-96.
PMID: 26106142 DOI: 10.1093/carcin/bgv039

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.