Predictors of Plasma Levels of Direct Oral Anticoagulants Among Patients with Atrial Fibrillation in Need of Elective Cardiac Procedures

BACKGROUND

The withdrawal timing of direct oral anticoagulants (DOACs) among patients in need of elective invasive surgery is based on DOAC pharmacokinetics in order to perform the procedure out of the DOAC peak plasma concentration. We aimed to investigate the prevalence and predictors of plasma levels of DOACs out of trough range in patients with atrial fibrillation (AF) in need of elective cardiac procedure.

MATERIALS AND METHODS

We evaluated all consecutive AF patients on DOAC therapy in need of elective cardiac procedure, admitted to our division from January 2022 to March 2022. All patients underwent DOAC plasma dosing the morning of procedure day. They were categorized as in range, above range, and below range, according to the DOAC reference range at the downstream point. The timing of discontinuation of DOAC therapy was considered as appropriate or not, according to the current recommendations. The clinical predictors of out-of-range DOAC plasma levels have been evaluated.

RESULTS

We included 90 consecutive AF patients (56.6% male, mean age 72.95 ± 10.12 years); 74 patients (82.22%) showed DOAC concentration out of the expected reference range. In half of them (n, 37), the DOAC plasma concentration was below the trough reference range. Of the study population, 17.7% received inappropriate DOAC dosages (10% overdosing, 7% underdosing), and 35.5% had incorrect timing of DOAC withdrawal (26% prolonged, 9.5% shortened). At multivariable analysis, inappropriate longer DOAC withdrawal period (OR 10.13; P ≤ 0.0001) and increased creatinine clearance (OR 1.01; P = 0.0095) were the independent predictors of plasma DOAC levels below the therapeutic trough range. In contrast, diabetes mellitus (OR 4.57; P = 0.001) was the only independent predictor of DOAC plasma level above the therapeutic trough range.

CONCLUSION

Increased creatinine clearance and inappropriate longer drug withdrawal period are the only independent predictors of DOAC plasma levels below the reference range; in contrast, diabetes is significantly correlated with DOAC plasma levels above the reference.

Late Onset Occurrence of Concomitant Myocardial Infarction and Ischemic Stroke in Hospitalized COVID-19 Patient: A Case Report

We described the case of a 68-year-old COVID-19 patient with hypertension and dyslipidemia who discontinued the cardiovascular medications during hospitalization and experienced a late onset occurrence of concomitant ST-elevation myocardial infarction and ischemic stroke at resolution of SARS-CoV-2 pneumonia.

659 Myocardial infarcion and ischaemic stroke in a COVID-19 patient: nothing happens by chance

A 68-years-old man, affected by arterial hypertension in treatment with angiotensin-receptor blocker (cardesartan 32 mg), was admitted to emergency department for fever and dyspnoea. The molecular swab for SARS-CoV-2 was positive. Chest CT showed bilateral interstitial pneumonia with Chung severity score index 15/20. The laboratory examinations showed: PCR 21 mg/dl, IL-6 17 pg/ml, d-dimer 374 ng/ml, lymphopenia, glycaemia 218 mg/dl, total cholesterol 245 mg/dl. At COVID-19 diagnosis he started the following therapy: Azithromycin 500 mg once a day, Methylprednisolone 20 mg twice a day, Remdesivir 200 mg once a day, Enoxaparin 6000 UI twice a day, Insulin Lispro 6/8/8 UI three times a day, High FlowNasal Cannula (FiO₂ 45%). No lipid-lowering therapy was prescribed. During the hospitalization, the patient experienced a progressive improvement in clinical and laboratory parameters. On the 28th day, there was a sudden worsening of dyspnoea with evidence of ST-elevation in DI, aVL, V2–V6 leads. A primary percutaneous coronary intervention at COVID-19 HUB hospital (2.9 km away) was required. Because of massive demand for emergency vehicles, the patient was admitted to the Chat Lab 3 h and 23 min later. Due to evidence of critical stenosis of the proximal and intermediate left anterior descending artery, a PTCA with stenting was performed. 12 h later, the patient developed left hemiplegia (NIHSS score: 7). The brain CT revealed an acute right frontal ischaemic lesion; no indication to fibrinolysis was given by the consultant neurologist. Our case report describes the rare concomitance of two thrombotic events in a COVID-19 patient with many cardiovascular risk factors, offering the opportunity to underline the need of their appropriate treatment during the hospitalization for SARS-CoV-2 infection. Moreover, a dedicated treatment pathways should be provided for COVID-19 patients in order to ensure the timely and correct application of the protocols suggested by the international guidelines. 659 Figure 1

Heart rate variability as a measure of autonomic nervous system function in anorexia nervosa

BACKGROUND AND HYPOTHESIS

Alteration in sympathovagal balance may be a mechanism of increased cardiovascular mortality and sudden death of patients with anorexia nervosa. This study was undertaken to characterize cardiac autonomic control in patients with anorexia nervosa by means of heart rate variability analysis.

METHODS

Heart period variability by 24-h Holter recording was evaluated in 13 young women with anorexia nervosa, 10 constitutionally thin women, and 10 women of normal weight.

RESULTS

High-frequency power, a measure of parasympathetic modulation of heart rate, and all-time domain measures of heart rate variability were higher in patients with anorexia nervosa than in thin women and in those of normal weight. Thin women showed lower values of total power and of most components of power spectrum.

CONCLUSIONS

Our data demonstrate an increased vagal tone in young women with anorexia nervosa. The marked increase in parasympathetic activity, not in response to an increase in sympathetic activity, could be detrimental and may contribute to the higher cardiovascular mortality of these patients.

Intensive training and cardiac autonomic control in high level athletes

PURPOSE

We aimed to evaluate in a longitudinal study the effect of intensive training on cardiac autonomic control in athletes using 24-h heart rate variability analysis.

METHODS

Time and frequency domain measures of heart rate variability were calculated from 24-h Holter monitoring in 15 high level bicyclists (mean age 21 +/- 4 yr) after 1 month of detraining and after 5 months of vigorous training. At the same times echocardiographic left ventricular mass and dimensions and maximal oxygen consumption (VO2max) were assessed.

RESULTS

In detrained athletes, VO2max values, left ventricular mass and dimensions, and time and frequency domain measures of vagal modulation of heart rate were higher than in a group of untrained subjects of similar age while heart rate and the low-to-high frequency ratio were lower, indicating an enhanced vagal modulation of heart rate in athletes as compared with that in control subjects. After 5 months of vigorous training, left ventricular mass and dimensions and VO2max increased in athletes, while heart rate decreased further. In contrast, no changes were detectable in time and frequency domain measures of heart rate variability over the entire 24-h and in both waking and sleeping hours.

CONCLUSIONS

This study demonstrates that an increased cardiac vagal control is detectable in detrained athletes; however, after intensive training, despite a significant decrease in heart rate, time and frequency domain measures of heart rate variability reflecting cardiac vagal control remain unchanged. Thus, other mechanisms than changes in cardiac autonomic control could be involved in determining the profound bradycardia of athletes.

Twenty-four-hour blood pressure monitoring during treatment with extended-release felodipine versus slow-release nifedipine in elderly patients with mild to moderate hypertension: a randomized, double-blind, cross-over study

OBJECTIVE

This double-blind, placebo-controlled randomized study was designed to compare the antihypertensive effect and tolerability of extended-release felodipine and slow-release nifedipine retard in elderly hypertensive patients.

METHODS

Thirty patients of both sexes (mean age 71 years) with mild to moderate essential hypertension were recruited from our hypertension outpatient clinic. After a 2-week placebo period, felodipine extended-release (felodipine ER), 10 mg once daily, nifedipine slow-release retard (nifedipine SR), 20 mg twice daily or placebo were administered to each patient for 2 weeks according to a 3 x 3 latin-square design. At the end of each treatment period, the patients underwent 24-h noninvasive blood pressure monitoring.

RESULTS

All of the patients completed the trial and no serious adverse experience was reported. In comparison with placebo, felodipine and nifedipine decreased mean 24-h diastolic blood pressure by 6.7 and 4.3 mmHg, respectively, with no significant difference between the two drugs. Mean 24-h systolic blood pressure also decreased after felodipine and nifedipine, with no difference between the two drugs. Both drugs reduced blood pressure variability, lowering the 24-h mean standard deviation of mean hourly blood pressure values. The trough:peak ratio for felodipine was 80% for systolic and 75% for diastolic blood pressure.

CONCLUSION

Felodipine ER once daily lowers blood pressure in elderly hypertensives and is as effective as nifedipine SR twice daily. The high trough:peak ratio suggests that the dose and the between-dose interval of felodipine provides adequate therapeutic coverage.

Heart rate variability in patients with hypertrophic cardiomyopathy: association with clinical and echocardiographic features

Autonomic dysfunction has been reported in patients with hypertrophic cardiomyopathy. To evaluate the influence of different clinical and echocardiographic features of the disease on sympathovagal balance, as assessed by heart rate variability, 33 patients with hypertrophic cardiomyopathy and 33 healthy volunteers underwent echocardiographic examination and 24-hour electrocardiogram Holter recording. Measures of vagal modulation of heart rate were lower in patients with hypertrophic cardiomyopathy than in controls, particularly in those exhibiting syncope, exertional chest pain, dyspnea, or moderate or severe mitral regurgitation. Furthermore, the age-corrected multiple regression analysis showed that the parasympathetic cardiac control was inversely related to left atrial dimension and directly related to left ventricular end-systolic dimension. Therefore in hypertrophic cardiomyopathy the parasympathetic withdrawal is more evident in patients with symptoms than in those without; the reduction in left ventricular end-systolic dimension and the increase in left atrial size are the echocardiographic features that most influence the sympathovagal balance.

Comparison of verapamil versus felodipine on heart rate variability after acute myocardial infarction

A depressed heart rate variability (HRV) is a powerful predictor of poor outcome in myocardial infarction patients. The beneficial effect of specific interventions on its recovery has been reported, but data concerning calcium antagonists are scarce. We evaluated the effect of a phenylalkylamine derivative, verapamil, and a dihydropyridine derivative, felodipine, on time- and frequency-domain measurements of HRV by 24-hour Holter monitoring in 60 patients with acute myocardial infarction (AMI). After a first Holter recording (65 +/- 8 hours from the onset of symptoms), patients were randomly assigned to continue standard treatment or to also receive verapamil retard (120 mg 3 times daily) or felodipine extended-release (10 mg/day). Holter recording was repeated after 7 days. After verapamil, mean RR interval increased from 823 +/- 92 to 907 +/- 95 ms and the SD of all normal RR (NN) intervals (SDNN) from 99 +/- 24 to 120 +/- 30 ms (p < 0.01); the root mean square successive difference (r-MSSD) and the percent of differences between adjacent NN intervals > 50 ms (pNN50) also increased (p < 0.01). After felodipine, only SDNN increased (p < 0.01). Regarding frequency-domain measurements, after receiving verapamil, very low frequency, low- and high-frequency powers increased (p < 0.01), whereas the low- to high-frequency ratio decreased (p < 0.01). After receiving felodipine, very low-frequency power increased (p < 0.01), whereas low- and high-frequency powers and the low- to high-frequency ratio remained unchanged. This study demonstrates that verapamil, but not felodipine, improves HRV in the early phase after AMI.

Incremental prognostic value of thallium reinjection after stress-redistribution imaging in patients with previous myocardial infarction and left ventricular dysfunction

This study evaluated the incremental prognostic value of 201TI reinjection imaging over clinical, exercise and thallium stress-redistribution data in patients with previous myocardial infarction and left ventricular dysfunction.

METHODS

Thallium-201 reinjection after stress-redistribution SPECT was performed in 104 consecutive patients with a first Q-wave myocardial infarction (> 8 wk) and left ventricular ejection fraction < or = 40%. Follow-up data (mean 22 mo) were available for 98 patients; 16 patients underwent early revascularization procedures within 3 mo after exercise testing and were not considered for the analysis.

RESULTS

During follow-up there were 13 hard events (cardiac death and myocardial infarction) and 11 soft events (coronary revascularization procedures > 3 mo after thallium imaging). With multivariate Cox regression analysis, the sum of defects at stress-redistribution imaging that were reversible or moderate irreversible after reinjection was a powerful predictor of subsequent events. The addition of thallium reinjection imaging data significantly improved the prognostic power of clinical, exercise and stress-redistribution data for the occurrence of hard events (p < 0.01).

CONCLUSION

In patients with previous myocardial infarction and left ventricular dysfunction, thallium reinjection imaging provides incremental prognostic information over those obtained from conventional stress-redistribution imaging.