A 65-year-old male farmer presented to our hospital with complaints of nausea, vomiting, chest tightness, and chest pain in March 2020. Three hours prior to presentation, the patient consumed 400 mL of chlorpyrifos in an attempt to commit suicide. Then, he presented with nausea, vomiting, sweating, and muscle tremors accompanied by slight chest tightness and pain. After he was found by his family, the patient was immediately sent to a local community hospital where gastric lavage was carried out and 10 mg of atropine was intravenously injected. However, the symptoms were not resolved, and his chest pain worsened. For further treatment, he was transferred to our hospital. His medical history included hypertension for 20 years and coronary heart disease for half a year. Six months ago, the patient underwent percutaneous coronary intervention (PCI), during which, a stent was implanted in the left anterior descending coronary artery. He consumed alcohol occasionally and had a 20-year history of smoking and smoked 40 cigarettes per day.
On physical examination, the patient was restless. His axillary temperature was 36.9 C, blood pressure was 145/100 mmHg, heart rate was 105 beats/min (bpm), and respiratory rate was 20 breaths/min. The diameters of both pupils were 4 mm. His heartbeat was fast and regular, without a murmur, and his upper abdomen was mildly tender. The skeletal muscle of the extremities went into spasm, with an increased muscle tone. The lungs were clear, and the neurologic examination was unremarkable.
In the coagulation analysis, the international normalized ratio was 1.52, and the D-dimer level was 1.044 mug/mL. Cholinesterase level was 498 U/L, NT-pro BNP was 3,667.4 pg/mL, cardiac troponin I was 1.005 ng/mL, creatine kinase was 526 U/L, creatine kinase isoenzyme-MB was 34 U/L, alpha-hydroxybutyric dehydrogenase was 220 U/L, and lactate dehydrogenase was 282 U/L. Levels of electrolytes, as well as tests for liver and renal function, were within normal limits. As shown in Figure 1A, an electrocardiogram taken at the local community hospital showed a symmetrical negative T wave in leads V1-V6 and an upsloping ST-segment at the J point continuing into positive symmetrical T waves in leads II, III, and aVF. Chest radiography and abdominal ultrasound revealed no obvious abnormalities.
Based on the above clinical manifestations, medical history, result of auxiliary examinations, and level of serum biomarkers, the patient was conclusively diagnosed with an acute non-ST-segment elevation MI, severe chlorpyrifos poisoning, and grade 1 hypertension (very-high-risk group).
After admission to the cardiac care unit, the patient received oxygen by nasal cannula. Because the patient and his family refused coronary intervention, pharmacologic treatment was provided instead. For AMI, the patient was orally administered with 180 mg of ticagrelor, 0.3 g of aspirin, 10 mg of rosuvastatin calcium, and 25 mg of metoprolol tartrate. For hypertension, oral valsartan (40 mg) in the form of dispersible tablets was given. For chlorpyrifos poisoning, he was treated using an intravenous injection of 2 g of pralidoxime iodide for the revitalization of cholinesterase. Additionally, parenteral nutrition support and 40 mg of pantoprazole sodium injection for rehydration, maintenance of nutrition, and protection of gastric mucosa were provided. On the following day, his chest pain diminished. However, he reported an obvious upper abdominal pain, accompanied by tarry stools. Considering that the bedside abdominal ultrasound revealed none of the clinically significant findings, he was treated with 8 mg of norepinephrine tartrate injection and 2 g of oral sucralfate tablets to control the gastrointestinal bleeding and protect the gastric mucosa. As shown in Figure 2, his heart rate dropped to 79 bpm after taking metoprolol tartrate tablets. A low dose of atropine and metoprolol tartrate was simultaneously adjusted to maintain the heart rate to <90 bpm. At night, he developed a fever of 38.6 C. A routine blood test revealed that his WBC count was 6,200 per cubic millimeter, with 73.9% of neutrophils, 14.1% of lymphocytes, and 12.0% of monocytes. His hemoglobin level was 12.8 g/dL. The patient was treated with an injection of 0.9 g of lysine acetylsalicylate and 3 g of cefoperazone sodium.
On day 4 of admission, his abdominal pain eased. Re-examination of the electrocardiogram revealed a normal sinus rhythm and the T-wave inversion in leads V1-V4 disappeared, without a pathological Q wave (Figure 1B). The patient was allowed to consume some liquid food, and the infusion volume was reduced. On day 5 of admission, cholinesterase levels rose from 498 to 4,476 U/L (Figure 3A), and cardiac troponin I decreased from 1.005 to 0.134 ng/mL (Figure 3B). Due to economic reasons, the patient and his family expressed a strong desire to be sent home for further rehabilitation. He continued taking aspirin, ticagrelor, and rosuvastatin after discharge. When followed-up on August 26, 2020, his condition was stable, and delayed encephalopathy was not observed.