Central and Peripheral Hemodynamics in Young Adults Who Use Water Pipes and the Acute Effects of Water-Pipe Use.

BACKGROUND: Tobacco use via water pipe (commonly referred to as water-pipe smoking [WPS]) is popular among young adults globally and exposes those who smoke to toxicants. RESEARCH QUESTION: Is WPS associated with impaired measures of arterial function and does WPS acutely impair these measures in young adults? STUDY DESIGN AND METHODS: We assessed heart rate (HR), brachial and aortic BP, HR-adjusted augmentation index (AI), and carotid-femoral pulse wave velocity (CFPWV) in 62 individuals who use water pipes and 34 individuals who have never used a water pipe recruited from the community (mean age, 22.5 ± 3.0 years; 48% female). Measurements were obtained before and after an outdoor session of WPS among participants who use water pipes and among the control group of participants who have never used a water pipe. Measurements were compared after vs before exposure and between those who use and those who do not use water pipes, adjusting for possible confounders using linear regression. RESULTS: Participants who use water pipes and control participants had similar demographic characteristics. BP and HR increased acutely after WPS (brachial systolic BP by 4.13 mm Hg [95% CI, 1.91-6.36 mm Hg]; aortic systolic BP by 2.31 mm Hg [95% CI, 0.28-4.33 mm Hg]; brachial diastolic BP by 3.69 mm Hg [95% CI, 1.62-5.77 mm Hg]; aortic diastolic BP by 3.03 mm Hg [95% CI, 0.74-5.33 mm Hg]; and HR by 7.75 beats/min [95% CI, 5.46-10.04 beats/min]), but not in the control group. AI was significantly higher in participants who use water pipes compared with those who do not (9.02% vs 3.06%; P = .03), including after adjusting for BMI and family history of cardiovascular disease (ß = 6.12; 95% CI, 0.55-11.69; P = .03) and when assessing habitual tobacco use via water-pipe extent (water pipes used/day × water-pipe use duration) in water-pipe-years (ß = 2.51/water-pipe-year; 95% CI, 0.10-4.92/water-pipe-year; P = .04). However, CFPWV was similar in those who use water pipes and those who do not, and AI and CFPWV did not change acutely after WPS. INTERPRETATION: In apparently healthy young individuals from the community, habitual WPS was associated with increased AI, a predictor of cardiovascular risk, and one WPS session acutely increased HR and brachial and aortic BP.

Founder Mutation in N Terminus of Cardiac Troponin I Causes Malignant Hypertrophic Cardiomyopathy.

BACKGROUND: Cardiac troponin I (TNNI3) gene mutations account for 3% of hypertrophic cardiomyopathy and carriers have a heterogeneous phenotype, with increased risk of sudden cardiac death (SCD). Only one mutation (p.Arg21Cys) has been reported in the N terminus of the protein. In model organisms, it impairs PKA (protein kinase A) phosphorylation, increases calcium sensitivity, and causes diastolic dysfunction. The phenotype of this unique mutation in patients with hypertrophic cardiomyopathy remains unknown. METHODS: We sequenced 29 families with hypertrophic cardiomyopathy enriched for pediatric-onset disease and identified 5 families with the TNNI3 p.Arg21Cys mutation. Using cascade screening, we studied the clinical phenotype of 57 individuals from the 5 families with TNNI3 p.Arg21Cys-related cardiomyopathy. We performed survival analysis investigating the age at first SCD in carriers of the mutation. RESULTS: All 5 families with TNNI3 p.Arg21Cys were from South Lebanon. TNNI3 p.Arg21Cys-related cardiomyopathy manifested a malignant phenotype-SCD occurred in 30 (53%) of 57 affected individuals at a median age of 22.5 years. In select carriers without left ventricular hypertrophy on echocardiogram, SCD occurred, myocyte disarray was found on autopsy heart, and tissue Doppler and cardiac magnetic resonance imaging identified subclinical disease features such as diastolic dysfunction and late gadolinium enhancement. CONCLUSIONS: The TNNI3 p.Arg21Cys mutation has a founder effect in South Lebanon and causes malignant hypertrophic cardiomyopathy with early SCD even in the absence of hypertrophy. Genetic diagnosis with this mutation may be sufficient for risk stratification for SCD.

Diabetes without Manifest Cardiovascular Disease: A Novel Approach in Risk Stratification and Treatment Selection.

BACKGROUND: Cardiovascular disease (CVD), the main macro vascular complication of type 2 diabetes (T2D), increases the risk of death significantly in patients with T2D. INTRODUCTION: Most of the patients with T2D do not have obvious CVD symptoms. Due to the paucity of data, CVD screening in asymptomatic patients with T2D remains highly controversial. METHODS: This has driven a panel of experts to establish a novel consensus on how to approach patients with T2D at high CVD risk. The panel formulated a stepwise algorithm by which patients with T2D undergo initial risk stratification into low, intermediate and high risk using the ASCVD calculator. In patients with intermediate risk, coronary artery calcium measurement is used to further stratify those patients into new low and high-risk categories. RESULTS AND CONCLUSION: The panel recommends using standard diabetes care in low risk patients and using SGLT2 inhibitors and GLP1 agonists with cardio protective effect, on top of standard care, in high risk individuals.

Non-familial cardiomyopathies in Lebanon: exome sequencing results for five idiopathic cases.

BACKGROUND: Cardiomyopathies affect more than 0.5% of the general population. They are associated with high risk of sudden cardiac death, which can result from either heart failure or electrical abnormalities. Although different mechanisms underlie the various types of cardiomyopathies, a principal pathology is common to all and is usually at the level of the cardiac muscle. With a relatively high incidence rate in most countries, and a subsequent major health burden on both the families and governments, cardiomyopathies are gaining more attention by researchers and pharmaceutical companies as well as health government bodies. In Lebanon, there is no official data about the spectrum of the diseases in terms of their respective prevalence, clinical, or genetic profiles. METHODS: We used exome sequencing to unravel the genetic basis of idiopathic cases of cardiomyopathies in Lebanon, a relatively small country with high rates of consanguineous marriages. RESULTS: Five cases were diagnosed with different forms of cardiomyopathies, and exome sequencing revealed the presence of already documented or novel mutations in known genes in three cases: LMNA for an Emery Dreifuss Muscular Dystrophy case, PKP2 for an arrhythmogenic right ventricle dysplasia case, and MYPN for a dilated cardiomyopathy case. Interestingly two brothers with hypertrophic cardiomyopathy have a novel missense variation in NPR1, the gene encoding the natriuretic peptides receptor type I, not reported previously to be causing cardiomyopathies. CONCLUSION: Our results unravel novel mutations in known genes implicated in cardiomyopathies in Lebanon. Changes in clinical management however, require genetic profiling of a larger cohort of patients.

Variations in the referral patterns to stress nuclear imaging and stress echocardiography scans.

BACKGROUND: Stress myocardial perfusion imaging (MPI) and stress echocardiography (Echo) are commonly used for the noninvasive evaluation of patients with suspected coronary artery disease (CAD). Very few studies have compared the referral patterns to these imaging modalities in terms of the clinical profile of patients, reasons for referral, and type of referring physicians. METHODS AND RESULTS: This was a prospective study of 1,020 consecutive patients who were referred for stress MPI (429 patients) or stress Echo (591 patients) at the American University of Beirut Medical Center in the year of 2008. Patients referred to MPI were older and had a higher prevalence of diabetes, hypertension, hypercholesterolemia, smoking, and previous myocardial infarction, coronary angioplasty, or bypass surgery. There were more abnormal scans in the stress MPI group (24% vs 15%, P < 0.001), as well as a higher prevalence of ischemia (15% vs 7.6%, P < 0.001) and impaired left ventricular function with an ejection fraction <50% (11% vs 1.7%, P < 0.001). A higher percentage of stress Echo studies were self-referred by physicians who themselves interpret the scans (31% vs 19%, P < 0.001). CONCLUSION: Patients referred for stress MPI are at a higher risk than those referred for stress Echo having more CAD risk factors, more prior history of coronary events, and an older age. These findings have important implications in the interpretation of studies that compare the diagnostic and prognostic power of these two imaging modalities.

International variations in the ischemic burden post-acute myocardial infarction: prognostic implications.

OBJECTIVES: To determine if there is a variation in the ischemic burden post-acute myocardial infarction (AMI), as assessed by myocardial perfusion imaging (MPI), between different populations in different geographic locations and to see if this variation is associated with different clinical outcomes. METHODS AND RESULTS: We characterized the MPI findings in 104 stable patients who were hospitalized with AMI at the American University of Beirut Medical Center (AUBMC), a tertiary referral hospital in an East Mediterranean country and we compared them to 126 patients who were enrolled according to a similar protocol in a previous study done at Baylor College of Medicine (BCM), Houston, Texas. There were no differences between the two populations with respect to prevalence of diabetes, hypertension, smoking, the use of thrombolysis, percentage of anterior MIs, Q-wave MIs, and multivessel disease on coronary angiography. However, the quantified ischemic defect size in the BCM population was double that in the AUBMC population (12 +/- 12% vs 6 +/- 8%, P < .01). This was associated with almost doubling of the 1 year event rate of death/myocardial infarction (18.3% vs 10.6%, P = .02) in the BCM population. CONCLUSION: Our study suggests that the ischemic burden post-AMI, as assessed by MPI, might vary between different populations in different geographic locations. This variation carries important prognostic implications and is associated with different patient outcomes.

[Epidemiology of cardiac tumors in adults in Lebanon]. / Epidémiologie des tumeurs cardiaques des adultes au Liban.

Primary cardiac tumors are rare but potentially fatal. No studies have discussed this issue yet on the national level. We describe the epidemiology of cardiac tumors in adults in Lebanon. The data were taken from the hospitals, the patients and/or their doctors by means of a questionnaire. Fifty-seven cases of cardiac tumors were found, mainly myxomas in the left atrium. Dyspnea was the most frequent symptom. Transthoracic echocardiography was the main diagnostic tool. Transesophageal echocardiography was inconstantly made, scanner and MRI rarely while contrast echocardiography has never been used. Almost half of the patients had a follow-up and none had a familial screening. The collected data urged us to propose a unique and homogenous strategy for diagnosis, treatment and follow-up of cardiac tumors in Lebanon.

Bilateral percutaneous stent implantation in the pulmonary vasculature: a modality now available in Lebanon.

We report a child with Truncus Arteriosus who developed bilateral proximal branch pulmonary stenosis, following total surgical repair of her condition with construction of the right ventricular outflow tract utilizing a Contegra conduit (Medtronic Inc., Minneapolis, Minn.). The obstruction was relieved completely utilizing bilateral percutaneous stent implantation. To the best of our knowledge, this is the first reported case of bilateral stent implantation to relieve branch pulmonary artery stenosis in Lebanon. This technique could be applied to similar cases of obstruction in the pulmonary tree.