Pulmonary embolism in COVID-19: Clinical characteristics and cardiac implications.

BACKGROUND: The thrombogenic potential of Covid-19 is increasingly recognised. We aim to assess the characteristics of COVID-19 patients diagnosed with pulmonary embolism (PE). METHODS: We conducted a single centre, retrospective observational cohort study of COVID-19 patients admitted between 1st March and 30th April 2020 subsequently diagnosed with PE following computed tomography pulmonary angiogram (CTPA). Patient demographics, comorbidities, presenting complaints and inpatient investigations were recorded. RESULTS: We identified 15 COVID-19 patients diagnosed with PE (median age = 58 years [IQR = 23], 87% male). 2 died (13%), both male patients >70 years. Most common symptoms were dyspnoea (N = 10, 67%) and fever (N = 7, 47%). 12 (80%) reported 7 days or more of non-resolving symptoms prior to admission. 7 (47%) required continuous positive airway pressure (CPAP), 2 (13%) of which were subsequently intubated. All patients had significantly raised D-dimer levels, lactate dehydrogenase (LDH), C-reactive protein (CRP), ferritin and prothrombin times. The distribution of PEs correlated with the pattern of consolidation observed on CTPA in 9 (60%) patients; the majority being peripheral or subsegmental (N = 14, 93%) and only 1 central PE. 10 (67%) had an abnormal resting electrocardiogram (ECG), the commonest finding being sinus tachycardia. 6 (40%) who underwent transthoracic echocardiography (TTE) had structurally and functionally normal right hearts. CONCLUSION: Our study suggests that patients who demonstrate acute deterioration, a protracted course of illness with non-resolving symptoms, worsening dyspnoea, persistent oxygen requirements or significantly raised D-dimer levels should be investigated for PE, particularly in the context of COVID-19 infection. TTE and to a lesser degree the ECG are unreliable predictors of PE within this context.

Should all patients receive extended thromboprophylaxis after resection of primary lung cancer?

OBJECTIVE: The optimal duration of thromboprophylaxis in patients undergoing resection of primary lung cancer is not known. We investigated the incidence of pulmonary emboli and venous thromboembolism in patients undergoing early-stage lung cancer resection and the impact of change from short duration to extended thromboprophylaxis. METHODS: We reviewed the outcomes of consecutive patients who underwent resection of early-stage primary lung cancer following a change in protocol from inpatient-only to extended thromboprophylaxis to 28 days. Propensity-score matching of control (routine inpatient pharmacologic thromboprophylaxis) and treatment group (extended pharmacologic thromboprophylaxis) was performed. Adjustment for covariates based on the Caprini risk assessment model was undertaken. Thromboembolic outcomes were compared between the 2 groups. RESULTS: Seven hundred fifty consecutive patients underwent resection of primary lung cancer at Oxford University Hospitals NHS Foundation Trust between January 2013 and December 2018. Six hundred patients were included for analysis and propensity-score matching resulted in 253 matched pairs. Extended prophylaxis was associated with a significant reduction in pulmonary emboli (10 of 253 patients [4%] vs 1 of 253 patients [0.4%], P = .01). One patient (0.4%) developed a bleeding complication within the treatment cohort. Multivariable logistic regression model demonstrated that extended thromboprophylaxis was independently associated with a reduction in postoperative pulmonary emboli. CONCLUSIONS: Patients undergoing lung cancer resection surgery are at moderate-to-high risk of postoperative thromboembolic disease. Extended dalteparin for 28 days is safe and is associated with reduced incidence of pulmonary embolus in patients undergoing resection of early-stage primary lung cancer.

Donepezil induces ventricular arrhythmias by delayed repolarisation.

Acetylcholinesterase inhibitors such as donepezil delay the progression of Alzheimer's dementia by increasing acetylcholine concentrations in the central nervous system. However, it is becoming apparent that cholinesterase inhibition by donepezil is not confined to the brain. This is supported by previous case reports of peripheral cholinergic side effects and adverse cardiac arrhythmias such as Torsades de Pointes which are reversible upon cessation of donepezil. The augmented acetylcholine concentrations and IKr inhibition in cardiomyocytes caused by donepezil are believed to mediate this effect.

Elevated procalcitonin concentrations in severe Covid-19 may not reflect bacterial co-infection.

BACKGROUND: The variability of Covid-19 severity between patients has driven efforts to identify prognosticating laboratory markers that could aid clinical decision-making. Procalcitonin is classically used as a diagnostic marker in bacterial infections, but its role in predicting Covid-19 disease severity is emerging. We aimed to identify the association between procalcitonin and Covid-19 disease severity in a critical care setting and whether bacterial co-infection is implicated. METHODS: We retrospectively reviewed Covid-19 patients with procalcitonin concentrations measured in a critical care setting at our institution between February and September 2020. Laboratory markers including peak procalcitonin values and a range of bacterial culture results were analysed. Outcomes were the requirement and duration of invasive mechanical ventilation as well as inpatient mortality. RESULTS: In total, 60 patients were included; 68% required invasive mechanical ventilation and 45% died as inpatient. Univariate analysis identified higher peak procalcitonin concentrations significantly associated with both the requirement for invasive mechanical ventilation (OR: 3.2, 95% CI 1.3-9.0, P = 0.02) and inpatient mortality (OR: 2.6, 95% CI 1.1-6.6, P = 0.03). Higher peak procalcitonin concentrations was an independent predictor of mortality on multivariate analysis (OR 3.7, 95% CI 1.1-12.4, P = 0.03). There was a significant positive correlation between increased peak procalcitonin concentrations and duration on invasive mechanical ventilation. No significant difference was found between peak procalcitonin concentrations of patients with positive and negative bacterial cultures. CONCLUSIONS: Elevated procalcitonin concentrations in Covid-19 patients are associated with respiratory failure requiring prolonged invasive mechanical ventilation and inpatient mortality. This association may be independent of bacterial co-infection.

Long term use of donepezil and QTc prolongation.

BACKGROUND: The neurocognitive benefits of donepezil are well recognised, but the potential side effects on cardiac conduction remain unclear. OBJECTIVE: To investigate whether long-term donepezil therapy is associated with electrocardiographic (ECG) changes and in particular to assess its effects on the QT interval. METHODS: We conducted a single centre retrospective analysis of patients admitted to our trust on donepezil therapy over a 12-month period. An admission resting 12-lead ECG was obtained and compared to their ECG prior to commencement of donepezil therapy to assess for any significant difference in ECG parameters. RESULTS: We identified 59 patients suitable for analysis. PR (177.0 ± 29.0 ms vs. 186.1 ± 34.2 ms, p = 0.04), QRS (101.7 ± 20.3 ms vs. 104.7 ± 22.3 ms, p = 0.04) and QT (393.3 ± 35.6 ms vs. 411.9 ± 44.6 ms, p = 0.002) interval prolongation were all associated with donepezil use. The increase in QT intervals remained significant on correction for heart rate; resulting in 8 (13.6%) patients developing high arrhythmogenic risk based on assessment using QT nomogram plots. Concomitant use of tricyclic antidepressants was associated with significant QT prolongation (QTcB: r pb = 0.344, p = 0.008, QTcFred: r pb = 0.382, p = 0.003, QTcFram: r pb = 0.379, p = 0.003, QTcH: r pb = 0.352, p = 0.006), while the use of rate-limiting calcium channel blockers was associated with significant PR prolongation (r pb = 0.314, p = 0.030), and beta-blockers with a reduction in heart rate (r pb = 0.256, p = 0.050). CONCLUSION: Our results clearly demonstrate that long-term use of donepezil is associated with prolongation of the QT interval. We suggest ECG evaluation should take place before and after donepezil initiation, and clinicians should be even more vigilant in those prescribed tricyclic antidepressants.

Atypical presentation of COVID-19 in hospitalised older adults.

BACKGROUND: It is increasingly recognised that older patients may not present with typical symptoms of COVID-19. AIMS: This study aims to evaluate the incidence, characteristics and clinical outcome of older adults with atypical presentations of COVID-19. METHODS: A retrospective analysis of adults ≥ 65 years with confirmed COVID-19 admitted to our institution between 1 March and 24 April 2020 was performed. Patients were categorised into typical or atypical groups based on primary presenting complaint in the community. RESULTS: One hundred twenty-two patients (mean age 81 ± 8 years; 62 male) were included. Seventy-three (60%) were categorised into the typical group and 49 (40%) into the atypical group. In the atypical group, common presenting complaints were fall in 18 (36%), reduced mobility or generalised weakness in 18 (36%) and delirium in 11 (22%). Further assessment by paramedics and on admission found 32 (65%) to have typical features of COVID-19, fever being the most common, and 22 (44%) were hypoxic. This subset had worse outcomes than those in the typical group with a mortality rate of 50% versus 38%, respectively, although this was not statistically significant (P = 0.27). No significant difference in mortality or length of hospital stay between the groups was demonstrated. CONCLUSION: Older patients with atypical presentation of COVID-19 in the community are equally susceptible to poor outcomes. Early detection may improve outcomes and limit community transmission. Primary care practitioners should be vigilant and consider prompt onward referral.

Permanent pacemaker implantation rates following cardiac surgery in the modern era.

AIMS: The aim of this study was to evaluate the incidence of permanent pacemaker (PPM) implantation after cardiac surgery in our institution and investigate risk factors for PPM dependency to provide patients with accurate incidence figures at the time of consent for surgery. METHODS: Data was collected retrospectively from a single tertiary institution from October 2018 to April 2019 inclusive of 403 patients. Incidence of PPM implantation after various cardiac operations was evaluated. A univariate analysis was carried out to identify the independent risk factors related to PPM implantation. RESULTS: Ten patients required a PPM (2.48%). The most common indication for PPM implantation post-cardiac surgery was complete heart block (N = 7, 70%) followed by bradycardia/pauses (N = 2, 20%) and sick sinus syndrome (N = 1, 10%). PPM implantation after coronary artery bypass graft (CABG) surgery was the lowest (0.63%), while combined CABG and valve operations had the highest incidence (5.97%). Independent risk predictors for PPM implantation included female gender (p = 0.03), rheumatic heart disease (p = 0.008), pulmonary hypertension (p = 0.01), redo operations (p = 0.002), mitral valve procedures (p = 0.001), tricuspid valve procedures (p = 0.0003) and combined mitral and tricuspid valve procedures (p = 0.0001). Average length of intensive care unit (ICU)/high-dependency unit (HDU) stay was significantly prolonged for patients who required a PPM post-cardiac surgery. CONCLUSION: As clinicians, it can be challenging to provide our patients with accurate information on the risk of PPM implantation relative to their operation. A unit-specific data may be a more accurate method of informing our patients on this risk.