**5. Conclusions**

An increased risk of the daily emergency ambulance calls for elevated arterial blood pressure was associated both with a positive (>0.5) and a negative (<−1 or <−0.5) values of the NAO index, adjusting the impact of month and weather variables. The different impact of the NAO was found during the periods of November–March and April–October. The impact of the NAO index was not identical for different times of the day. No significant impact of the NAO index was observed during the period of 8:00–13:59. The stronger impact of NAOI < −0.5 and NAOI > 0.5 was found in the afternoon until the evening, especially during the colder period.

**Author Contributions:** J.V. conceived the idea, performed statistical analyses, interpreted the results and was the lead writer. P.D. was responsible for the medical data and read and approved the final manuscript. J.Z. was responsible for the analysis of NAO and this phenomenon impact on climate and air pollution. A.B. assisted with the writing of the manuscript and revised the manuscript. All authors read and approved the final version of the manuscript.

**Funding:** This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

**Acknowledgments:** We acknowledge the contribution of Kaunas city ambulances involved in the registration of cardiovascular emergency admissions and the formation of the computer database.

**Conflicts of Interest:** The authors declare no conflict of interest.
