Concentration-response relationships between hourly particulate matter and ischemic events: A case-crossover analysis of effect modification by season and air-mass origin.

Most studies linking cardiovascular disease with particulate matter (PM) exposures have focused on total mass concentrations, regardless of their origin. However, the origin of an air mass is inherently linked to particle composition and possible toxicity. We examine how the concentration-response relation between hourly PM exposure and ischemic events is modified by air-mass origin and season. Using telemedicine data, we conducted a case-crossover study of 1855 confirmed ischemic cardiac events in Israel (2005-2013). Based on measurements at three fixed-sites in Tel Aviv and Haifa, ambient PM with diameter < 2.5 µm (PM2.5) and 2.5-10 µm (PM10-2.5) concentrations during the hours before event onset were compared with matched control periods using conditional logistic regression that allowed for non-linearity. We also examined effect modification of these associations based on the geographical origin of each air mass by season. Independent of the geographical origin of the air mass, we observed concentration-response curves that were supralinear. For example, the overall odds ratios (ORs) of ischemic events for an increase of 10-µg/m3 in the 2-h average of PM10-2.5 were 1.08 (95% confidence interval (CI): 1.03-1.14) and 1.00 (0.99-1.01) at the median (17.8 µg/m3) and 95th percentile (82.3 µg/m3) values, respectively. Associations were strongest at low levels of PM10-2.5 when air comes from central Europe in the summer (OR: 1.27; 95% CI: 1.06, 1.52). Our study demonstrates that hourly associations between PM2.5 and PM10-2.5 and ischemic cardiac events are supralinear during diverse pollution conditions in a single population that experiences a wide range of exposure levels.

Fine and Coarse Particulate Matter Exposures and Associations with Acute Cardiac Events among Participants in a Telemedicine Service: A Case-Crossover Study.

BACKGROUND: Subclinical cardiovascular changes have been associated with ambient particulate matter (PM) exposures within hours. Although the U.S. Environmental Protection Agency continues to look for additional evidence of effects associated with sub-daily PM exposure, this information is still limited because most studies of clinical events have lacked data on the onset time of symptoms to assess rapid increased risk. OBJECTIVE: Our objective was to investigate associations between sub-daily exposures to PM and acute cardiac events using telemedicine data. METHODS: We conducted a case-crossover study among telemedicine participants [Formula: see text] of age who called a service center for cardiac-related symptoms and were transferred to a hospital in Tel Aviv and Haifa, Israel (2002-2013). Ambient [Formula: see text] and [Formula: see text] measured by monitors located in each city during the hours before the patient called with symptoms were compared with matched control periods. We investigated the sensitivity of these associations to more accurate symptom onset time and greater certainty of diagnosis. RESULTS: We captured 12,661 calls from 7,617 subscribers experiencing ischemic (19%), arrhythmic (31%), or nonspecific (49%) cardiac events. PM concentrations were associated with small increases in the odds of cardiac events. For example, odds ratios for any cardiac event in association with a [Formula: see text] increase in 6-h and 24-h average [Formula: see text] were 1.008 [95% confidence interval (CI): 0.998, 1.018] and 1.006 (95% CI: 0.995, 1.018), respectively, and for [Formula: see text] were 1.003 (95% CI: 1.001, 1.006) and 1.003 (95% CI: 1.000, 1.007), respectively. Associations were stronger when using exposures matched to the call time rather than calendar date and for events with higher certainty of the diagnosis. CONCLUSIONS: Our analysis of telemedicine data suggests that risks of cardiac events in telemedicine participants [Formula: see text] of age may increase within hours of PM exposures. https://doi.org/10.1289/EHP2596.

Evaluation of telehealth service for patients with congestive heart failure in the north of Israel.

AIMS: This research was conducted to evaluate the impact of a telehealth service on re-hospitalization of patients with congestive heart failure at New York Heart Association II-IV. METHODS AND RESULTS: The telehealth service for congestive heart failure patients was designed to follow the patients after their daily weighing and to provide a response in cases of non-compliance or deviation from baseline weight. A weighing scale was installed in the patient's house together with a communication module connected to the telemedicine control centre through a telephone line. The control centre is staffed by skilled nurses whose responses to patients are guided by programmed algorithm. Over a year, we evaluated the changes in the frequency of hospital admission and of primary care visits, and quality of life of 141 individuals who were eligible for the telehealth service for congestive heart failure. A decline was noted in the average number of hospitalizations per patient (from 4.7 to 2.6, p < 0.001). Scores of parameters of quality of life were improved (average score for first through fourth quarterly administration: 64, 50, 16, 16, p < 0.001 by the Minnesota Living with Heart Failure Questionnaire). CONCLUSIONS: During the year of use in telehealth service for congestive heart failure parameters of hospitalization were improved, together with parameters of quality of life.

Expediting Time from Symptoms to Medical Contact Utilizing a Telemedicine Call Center.

BACKGROUND: No definitive solution has been forthcoming for the often dangerously long interval between symptom onset and seeking medical care in the prehospital setting. We examined the implementation of telemedicine technology and characterization of its utilizers for its efficacy in reducing this possibly life-threatening time lag. MATERIALS AND METHODS: A retrospective observational study was performed on the working database of an operational telemedicine facility that included all subscribers. Time-to-contact measurements throughout 2012 were retrieved from its medical files, and data on age, gender, medical history, and main complaint were analyzed. RESULTS: Throughout 2012, 22,274 of a total of 46,556 calls (47.8%) were made ≤60 min from symptom onset. It is important that 26.9% of all calls (12,522/46,556) were made in <15 min. Significantly more males (10,794/22,229 [49%]) contacted in ≤60 min compared with females (11,480/24,327 [47%], p<0.03). Subjects <60 years of age (2,889/5,717 [51%]) called earlier than those >60 years (19,386/40,839 [47%], p<0.001). Patients with prior resuscitation and/or myocardial infarction contacted significantly more rapidly than those with other cardiac diseases. Over one-half of patients with cardiac complaints contacted the call center ≤60 min from symptom onset, as did those who suffered physical trauma, but not patients with gastrointestinal symptoms or pain elsewhere. CONCLUSIONS: A telemedicine system with rapid accessibility to a professional call center and prompt triage thereafter could be an additional promising strategy for shortening the interval between symptom onset and call for medical assistance. Implementation of a widespread telemedicine infrastructure may bridge the unmet gap between occurrence of symptoms to initiation of medical treatment.

Is telemedicine an answer to reducing 30-day readmission rates post-acute myocardial infarction?

BACKGROUND: Patients hospitalized for an acute myocardial infarction (AMI) are at risk for early readmission. Readmission rates in the community reportedly reach approximately 20%, and 30-day readmission rates have become a quality-of-care marker. Telemedicine is one strategy for improving clinical outcomes by offering real-time biometrics tracking and rapid intervention. We retrospectively assessed the 30-day readmission rate of post-AMI members of a telemedicine system. MATERIALS AND METHODS: All "SHL"-Telemedicine subscribers who sustained an AMI and those who became subscribers within 10 days from discharge post-AMI between 2009 and 2012 were assessed. Their files were reviewed for demographics, coronary risk factors, reasons for readmission, and discharge diagnoses. RESULTS: In total, 897 suitable patients (mean age, 62±14 years; 81% males) were included. They had made 3,318 calls to the monitor center for consultation. A mobile intensive care unit was dispatched for 158 patients, 64 were transported to the hospital, and 52 (5.8%) were readmitted (10 patients were readmitted twice). Thirty-five readmissions were for noncardiac reasons. Twelve patients had acute coronary syndrome (11 were revascularized). Readmission rates were higher in patients with repeat AMIs (11.9% versus 5.3% among those with no AMI history) and in females (9.6% versus 4.9% among males). Unlike published figures for the general population, there were no significant differences between readmitted and non-readmitted patients regarding diabetes, hypertension, or congestive heart failure. CONCLUSIONS: Telemedicine technology shows considerable promise for reducing 30-day readmission rates of post-AMI patients.

Telemedicine for diagnosing and managing paroxysmal atrial fibrillation in outpatients. The phone in the pocket.

BACKGROUND: Individuals who experience paroxysmal atrial fibrillation (PAF) are at risk of serious sequelae, including stroke. PAF episodes usually occur in out-of-hospital settings, and patients seek emergency services for differential diagnosis and treatment. METHODS: Medical records of all subscribers to a telemedical system ('SHL'-Telemedicine) who had one or more episodes of recurrent PAF managed by the call center between 2/2002 and 8/2009 were retrieved. Treatment protocol consisted of initial electrocardiographic confirmation of PAF and repeat electrocardiograms within 24h. Management was exclusively by telephonically transmitted recommendations (Group A) or also included intervention by the attending physician of a 'SHL'-Telemedicine mobile intensive care unit (Group B). RESULTS: A total of 649 cardiac patients (1886 PAF episodes) were enrolled. The leading complaint was palpitation (57%). The 576 Group A patients had 1667 objectively documented PAF episodes, of which 1326 (79.5%) were converted into sinus rhythm by following telephonically delivered instructions. Their mean heart rate decreased from 85±15 to 66±10beats per minute (bpm) (P<0.001). Heart rate remained unchanged (86±15bpm) for those who remained in PAF. The 160 Group B patients (218 PAF episodes) had a conversion rate of 70% (153/218). The heart rate in converted cases decreased from 92±24bpm to 68±21bpm compared to a decrease from 90±21bpm to 87±21bpm in non-converted cases (P<0.001). CONCLUSIONS: Telemedicine for rapid out-of-hospital diagnosis and provision of objective documentation and instructions for appropriate management of PAF is feasible and could avoid potential PAF-associated complications and unnecessary emergency room visits and hospitalizations.

New real-time loop recorder diagnosis of symptomatic arrhythmia via telemedicine.

BACKGROUND: One disadvantage of current loop recorders is the long interval between recording an electrocardiogram (ECG), establishing a diagnosis, and taking appropriate medical measures. The Cardio R loop recorder transmits cardiac recordings by cellular communication at the push of a button. Users can concomitantly relay symptoms, thereby providing a symptom/cardio-rhythm correlation. HYPOTHESIS: The Cardio R is capable of early detection of cardio-electrical events that could account for patients' symptoms. METHODS: This observational study was designed to evaluate patients who were referred from community physicians/cardiologists for evaluation of various cardiac symptoms that were not observed by regular office ECGs or traditional 24-hour Holter cardiac monitoring. Transmitted recordings were instantly displayed on a monitor for immediate diagnosis by the on-duty medical team at SHL-Telemedicine's call center. Abnormal tracings, especially when accompanied by symptoms selected from the prepared list, enabled the staff to instruct the subscriber, notify their physician, and/or dispatch a mobile intensive care unit to the scene. RESULTS: Between January 2009 and August 2010, there were 17 622 ECG transmissions received from 604 patients (age range, 10-95 years) who completed a 1-month trial with the Cardio R device. Palpitation, presyncope, and chest pain were the leading complaints. A disturbance in rhythm that could account for symptoms occurred during recording in 49% cases and was displayed within 7 minutes in 93% of them. No longer than 2 days elapsed from recording onset to diagnosis. CONCLUSIONS: The Cardio R device enables prompt ECG confirmation/exclusion of a probable arrhythmic cause of symptoms, enabling rapid intervention for cardiac-relevant complaints.

Telemedicine for post-myocardial infarction patients: an observational study.

"SHL" Telemedicine (established 1987 in Israel) provides professional care to subscribers who use cardiobeepers and contact its medical call center via telecommunication networks. The extended 6-month Acute Coronary Syndrome Israel Survey (ACSIS) 2004 involved all 26 intensive cardiac care units in Israeli hospitals. We compared the 1-year survival rates of the "SHL" Telemedicine subscribers and ACSIS participants who survived hospitalization after sustaining an acute myocardial infarction. The myocardial infarction data for the ACSIS cohort (3,899 patients) and the SHL Telemedicine cohort (699 subscribers) were provided for this study by the ACSIS executive and SHL's files, respectively. One-year mortality was ascertained by telephone contacts with patients or their relatives. Mortality at 1 year was 4.4% for the "SHL" patients and 9.7% for the ACSIS patients (p < 0.0001). The "SHL" cohort was significantly older (p < 0.0001) than the ACSIS cohort (mean age [+/-SD] 69 +/- 11 versus 63 +/- 13 years), had significantly more past myocardial infarctions (p < 0.001), more past strokes (p < 0.0032), more heart failure (p < 0.0001), more hypertension (p = 0.002), and more hyperlipidemia (p < 0.0001). Gender distribution and diabetes status were similar for both groups. In spite of having more risk factors than the ACSIS subjects, the "SHL" Telemedicine subscribers had significantly higher survival rates at 1 year compared to the ACSIS patients, whose outcome is consistent with that of the Western world. Availability of medical call centers in the out-of-hospital setting for patients with suspected cardiac symptoms improves their motivation to seek timely and appropriate medical assistance.

Vigilance, awareness and a phone line: 20 years of expediting CPR for enhancing survival after out-of-hospital cardiac arrest. The 'SHL'-Telemedicine experience in Israel.

OBJECTIVES: The only large-scale report (1988) by the Israeli national ambulance service Magen David Adom (MDA) on the outcome of cardiac arrest victims who underwent cardiopulmonary resuscitation (CPR) by paramedics called for more frequent and more promptly initiated CPR and shorter time to arrival of paramedic care to improve survival. We report the 1987-2007 experience of resuscitation of out-of-hospital cardiac arrest victims who were 'SHL'-Telemedicine subscribers and who underwent CPR by SHL-Telemedicine mobile intensive care units (MICUs) personnel or under their instructions. METHODS: 'SHL's records of MICU reports and specifics of CPR maneuvers and outcome of resuscitated patients, as recorded by its MICU physicians, were analyzed to determine whether the system enhanced survival. RESULTS: A total of 1810 'SHL'-Telemedicine subscribers (mean age 76+/-12 years [16-104], 67% males) were resuscitated after cardiac arrest, 597 (33%) were hospitalized and 279 (15.4%) were discharged alive. Factors associated with successful resuscitation included witnessed collapse and documented ventricular fibrillation upon MICU arrival. A history of diabetes, hyperlipidemia, stroke or advanced age adversely affected the outcome. Time from collapse to CPR initiation and duration of CPR correlated significantly with survival. Laymen instructed telephonically by the 'SHL'-Telemedicine center performed CPR on 121 patients: 13 (10%) survived to hospital discharge. CONCLUSIONS: 'SHL'-Telemedicine's policy of bi-monthly contact with its subscribers led to heightened awareness of warning signs and need for rapid summoning of medical assistance in the setting of out-of-hospital sudden cardiac arrest.

Teleconsultation for cardiac patients: a comparison between nurses and physicians: the SHL experience in Israel.

The absence of randomized studies on sufficiently large patient cohorts precludes the drawing of any firm conclusions on the comparative performance between nurses and physicians in transtelephonic triage and consultations and in diagnostic and management decision-making. We conducted such a comparative study at the SHL telemedicine facility. This facility also provides face-to-face medical management for its subscribers by means of mobile intensive care units (MICUs) staffed by physicians. The outcome of calls that came between 7:00 AM and 11:00 PM throughout the study year and that were handled at random by specially trained physicians (n = 15) or nurses (n = 35) were analyzed. Of 48,707 subscribers who fulfilled the study entry criteria 25,106 used the service at least once, producing 88,103 calls (81,817 handled by nurses and 6,286 by physicians). Teleconsultations were sufficient for most of the cases (80.13%). There were no significant differences between the performance of nurses and physicians regarding demographics (age, gender) and medical diagnoses of the applicants. The nurses' performance and decisions were comparable to those of physicians with respect to teleconsultations, medically justified dispatches of an MICU, repeated calls to the center and mortality during the week after the index call, although the duration of the physicians' telephone consultations was longer. Delegation of equal authority to nurses and physicians in triage and consultation in telecardiology results in equivalent and highly satisfactory medical care in a system in which subscribers receive service orchestrated from a single center of telecommunications.

Intravenous chlorpromazine for the emergency treatment of uncontrolled symptomatic hypertension in the pre-hospital setting: data from 500 consecutive cases.

BACKGROUND: Chlorpromazine is a dopamine-receptor antagonist antipsychotic agent. Because of its strong alpha-blocking and sedative actions, it has also been used as emergency therapy for extreme arterial hypertension. Published reports to date have included very small numbers of patients (i.e., 5-30). OBJECTIVES: To analyze data on almost 500 patients who received intravenous chlorpromazine for the emergency treatment of uncontrolled symptomatic hypertension in the pre-hospital setting. METHODS: We reviewed data from 496 consecutive patients who received intravenous chlorpromazine as emergency therapy for uncontrolled symptomatic hypertension. Chlorpromazine was injected intravenously. The dose was 1 mg every 2-5 minutes until the systolic pressure was < or =140 mmHg and the diastolic pressure < or =100 mmHg with alleviation of symptoms. RESULTS: The mean dose of chlorpromazine administered was 4.5 +/- 5 mg (range 1-50 mg). Only 33 patients (7%) required >10 mg. Chlorpromazine reduced systolic BP from 222.82 +/- 26.31 to 164.93 +/- 22.66 mmHg (P< 0.001) and diastolic BP from 113.5 +/-16.63 to 85.83 +/- 11.61 mmHg (P< 0.001). The sinus rate decreased from 97.9 +/- 23.5 to 92.2 +/- 19.7 beats per minute (P< 0.001). These results were achieved within the first 37 +/- 11 minutes. CONCLUSIONS: Intravenous chlorpromazine is safe and effective when used as emergency treatment for uncontrolled symptomatic hypertension.

Telecardiology for patients with chronic heart failure: the 'SHL' experience in Israel.

BACKGROUND: Patients with chronic heart failure characteristically have multiple hospital admissions for symptom control, deleteriously affecting their quality of life and imposing a burden on national healthcare costs. We assessed the effect of a novel transtelephonic monitoring and follow-up program on the admission rate and length of hospital stay as well as changes in their subjectively rated quality of life of patients with chronic heart failure. METHODS: This prospective 1-year study was conducted on compliant subscribers to 'SHL', a telecardiological service with >60,000 subscribers, who were admitted > or = 2 times during the previous year for recurrent pulmonary edema or deterioration in heart failure. Their heart rate, blood pressure and body weight measurements were now automatically transmitted daily to 'SHL"s data bank and added to stored and updated medical records. A questionnaire survey acquired information on their quality of life. RESULTS: The study cohort included 118 patients, mean age 75 years (range 49-89 years), 65% males, a II-IV class functional capacity and a 25% (range 10-39%) mean ejection fraction. There was a 66% reduction in the total hospitalization days (from 1623 in the year preceding study entry to 558 during the study period, p<0.0001). Although only 38/118 patients were hospitalized, most participants reported a significant subjective improvement in their quality of life. CONCLUSIONS: Data are provided to demonstrate that a transtelephonic system allowing primary care at the patient's home can significantly reduce hospitalization rate and length of stay and significantly enhance the quality of life of patients with chronic heart failure.

Safety of nitrate withdrawal in angina-free and hemodynamically stable patients with coronary artery disease.

STUDY OBJECTIVES: To assess the consequences of nitrate withdrawal in angina-free and hemodynamically stable coronary patients. DESIGN: Prospective, open, intervention study. SETTING: Cardiology outpatient clinic of a university-affiliated municipal hospital. PATIENTS: Angina-free patients who were hemodynamically stable for at least 3 months before study onset were enrolled. They were all regularly receiving nitrates for symptom control. Those with significant reasons to avoid stopping nitrates, such as heart failure (ejection fraction <35%) or high BP (> 160 mm Hg systolic and/or > 100 mm Hg diastolic), and noncompliant patients were excluded. INTERVENTIONS: After providing informed consent and undergoing an exercise test (whenever possible), the participants were randomized to abruptly discontinue (study group) or continue (control group) nitrate treatment. Follow-up continued for at least 3 months after study entry. MEASUREMENTS AND RESULTS: Eighty patients were randomized to the study group and 40 patients to the control group (mean age [+/- 1 SD], 65.5 +/- 11 years and 66.1 +/- 10.9 years, respectively; p = not significant). The first month, eight study patients (10%) had a recurrence of anginal symptoms, compared with one control subject (2.5%) [p = not significant]. All eight patients responded promptly and favorably to the resumption of nitrate administration. CONCLUSIONS: Nitrate administration can be safely discontinued in angina-free and hemodynamically stable coronary patients who receive this medication on a regular basis. If relapse of anginal symptoms occurs, it will be within 1 month following nitrate withdrawal, and will resolve satisfactorily with reinstatement of treatment.